ADF7242 [ADI]
Low Power IEEE 802.15.4/Proprietary GFSK/FSK Zero-IF 2.4 GHz Transceiver IC; 低功耗IEEE 802.15.4 /专有GFSK / FSK零中频的2.4 GHz收发器IC
| 型号： | ADF7242 |
| 厂家： | 
ADI |
| 描述： | Low Power IEEE 802.15.4/Proprietary GFSK/FSK Zero-IF 2.4 GHz Transceiver IC |
| 文件： | 总108页 (文件大小：1216K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Low Power IEEE 802.15.4/Proprietary
GFSK/FSK Zero-IF 2.4 GHz Transceiver IC
ADF7242
On-chip low power processor performs
FEATURES
Radio control
Packet management
Packet management support
Frequency range (global ISM band)
2400 MHz to 2483.5 MHz
Programmable data rates and modulation
IEEE 802.15.4-2006-compatible (250 kbps)
GFSK/FSK/GMSK/MSK modulation
50 kbps to 2000 kbps data rates
Low power consumption
Insertion/detection of preamble/SWD/CRC/address
IEEEE 802.15.4-2006 frame filtering
IEEEE 802.15.4-2006 CSMA/CA unslotted modes
Flexible 256-byte transmit/receive data buffer
IEEEE 802.15.4-2006 and GFSK/FSK SPORT modes
Fast settling automatic frequency control
Flexible multiple RF port interface
External PA/LNA support hardware
Switched antenna diversity support
Wake-up timer
19 mA (typical) in receive mode
21.5 mA (typical) in transmit mode (PO = 3 dBm)
1.7 μA, 32 kHz crystal oscillator wake-up mode
High sensitivity (IEEE 802.15.4-2006)
−95 dBm at 250 kbps
High sensitivity (0.1% BER)
−96 dBm at 62.5 kbps (GFSK)
−93 dBm at 500 kbps (GFSK)
−90 dBm at 1 Mbps (GFSK)
−87.5 dBm at 2 Mbps (GFSK)
Programmable output power
−20 dBm to +4.8 dBm in 2 dB steps
Integrated voltage regulators
1.8 V to 3.6 V input voltage range
Very few external components
Integrated PLL loop filter, receive/transmit switch, battery
monitor, temperature sensor, 32 kHz RC and crystal
oscillators
Flexible SPI control interface with block read/write access
Small form factor 5 mm × 5 mm 32-lead LFCSP package
APPLICATIONS
Wireless sensor networks
Excellent receiver selectivity and blocking resilience
Zero-IF architecture
Complies with EN300 440 Class 2, EN300 328, FCC CFR47
Part 15, ARIB STD-T66
Automatic meter reading/smart metering
Industrial wireless control
Healthcare
Wireless audio/video
Consumer electronics
ZigBee
Digital RSSI measurement
Fast automatic VCO calibration
Automatic RF synthesizer bandwidth optimization
FUNCTIONAL BLOCK DIAGRAM
ADF7242
4kB
PROGRAM
ROM
8-BIT
PROCESSOR
DAC
ADC
FSK
DEMOD
LNA1
2kB
PROGRAM
RAM
RADIO
CONTROLLER
DSSS
DEMOD
LNA2
256-BYTE
PACKET
RAM
ADC
DAC
AGC
OCL
AFC
CDR
PACKET
MANAGER
64-BYTE
BBRAM
256-BYTE
MCR
FRACTIONAL-N
RF SYNTHESIZER
GAUSSIAN FILTER
PRE-EMPHASIS FILTER
PA
WAKE-UP CTRL
SPI
GPIO
SPORT
IRQ
32kHz
RC
OSC
32kHz
XTAL
OSC
BATTERY
MONITOR
TEMPERATURE
SENSOR
26MHz
OSC
LDO × 4
BIAS
Figure 1
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2010 Analog Devices, Inc. All rights reserved.
ADF7242
TABLE OF CONTENTS
Features .............................................................................................. 1
IEEE 802.15.4-2006 Receive Timing and Control ..................... 50
Clear Channel Assessment (CCA)........................................... 51
Link Quality Indication (LQI).................................................. 52
IEEE 802.15.4 Automatic TX-to-RX Turnaround Mode...... 53
Applications....................................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 3
General Description......................................................................... 4
Specifications..................................................................................... 6
General Specifications ................................................................. 6
RF Frequency Synthesizer Specifications.................................. 6
Transmitter Specifications........................................................... 7
Receiver Specifications ................................................................ 8
Auxiliary Specifications............................................................. 11
Current Consumption Specifications ...................................... 12
Timing and Digital Specifications............................................ 13
Timing Diagrams........................................................................ 15
IEEE 802.15.4 TX SPORT Mode Timing Diagrams.............. 18
GFSK/FSK RX SPORT Mode Timing Diagrams ................... 18
Absolute Maximum Ratings.......................................................... 22
ESD Caution................................................................................ 22
Pin Configuration and Function Descriptions........................... 23
Typical Performance Characteristics ........................................... 25
Terminology .................................................................................... 34
Radio Controller............................................................................. 35
Sleep Modes................................................................................. 37
RF Frequency Synthesizer ............................................................. 38
RF Frequency Synthesizer Calibration .................................... 38
RF Frequency Synthesizer Bandwidth..................................... 38
RF Channel Frequency Programming..................................... 39
Reference Crystal Oscillator ..................................................... 39
Transmitter ...................................................................................... 40
Transmit Operating Modes....................................................... 40
Transmitter in IEEE 802.15.4-2006 Mode .............................. 40
IEEE 802.15.4 Automatic RX-To-TX Turnaround Mode..... 43
Transmitter in GFSK/FSK Mode.............................................. 43
Power Amplifier.......................................................................... 46
Receiver............................................................................................ 48
Receive Operating Modes ......................................................... 48
Receiver in IEEE 802.15.4-2006 Mode .................................... 48
Receiver Calibration................................................................... 49
IEEE 802.15.4 Frame Filtering, Automatic Acknowledge, and
Automatic CSMA/CA................................................................ 53
Receiver in GFSK/FSK Mode ................................................... 56
Receiver Radio Blocks ............................................................... 61
SPORT Interface............................................................................. 63
GFSK/FSK SPORT Mode.......................................................... 63
IEEE 802.15.4-2006 SPORT Mode........................................... 65
Device Configuration .................................................................... 66
Configuration Values Common to IEEE 802.15.4 and
GFSK/FSK Modes ...................................................................... 67
Configuration Values for GFSK/FSK Packet and SPORT
Modes........................................................................................... 67
Configuration Values for IEEE 802.15.4-2006 Packet and
SPORT Modes............................................................................. 68
RF Port Configurations/Antenna Diversity................................ 69
Auxillary Functions........................................................................ 70
Temperture Sensor..................................................................... 70
Battery Monitor .......................................................................... 70
Wake-Up Controller (WUC).................................................... 70
Transmit Test Modes.................................................................. 71
Serial Peripheral interface (SPI) ................................................... 72
General Characteristics ............................................................. 72
Command Access....................................................................... 72
Status Word ................................................................................. 72
Memory Map .................................................................................. 74
BBRAM........................................................................................ 74
Modem Configuration RAM (MCR) ...................................... 74
Program ROM ............................................................................ 74
Program RAM ............................................................................ 74
Packet RAM ................................................................................ 74
Memory Access............................................................................... 76
Writing to the ADF7242............................................................ 77
Reading from the ADF7242...................................................... 77
Downloadable Firmware Modules............................................... 80
Interrupt Controller ....................................................................... 81
Rev. 0 | Page 2 of 108
ADF7242
Configuration ..............................................................................81
Description of Interrupt Sources ..............................................82
Applications Circuits ......................................................................83
Register Map ....................................................................................87
Outline Dimensions......................................................................105
Ordering Guide .........................................................................105
REVISION HISTORY
7/10—Revision 0: Initial Version
Rev. 0 | Page 3 of 108
ADF7242
GENERAL DESCRIPTION
The ADF7242 is a highly integrated, low power, and high perfor-
mance transceiver for operation in the global 2.4 GHz ISM band. It
is designed with emphasis on flexibility, robustness, ease of use,
and low current consumption. The IC supports the IEEE 802.15.4-
2006 2.4 GHz PHY requirements as well as proprietary GFSK/
FSK/GMSK/MSK modulation schemes in both packet and data
streaming modes. With a minimum number of external compo-
nents, it achieves compliance with the FCC CFR47 Part 15,
ETSI EN 300 440 (Equipment Class 2), ETSI EN 300 328
(FHSS, DR > 250 kbps), and ARIB STD T-66 standards.
The ADF7242 features a flexible dual-port RF interface that can
be used with an external LNA and/or PA in addition to support-
ing switched antenna diversity.
The ADF7242 incorporates a very low power custom 8-bit
processor that supports a number of transceiver management
functions. These functions are handled by the two main mod-
ules of the processor; the radio controller and the packet manager.
The radio controller manages the state of the IC in various
operating modes and configurations. The host MCU can use
single byte commands to interface to the radio controller. The
packet manager is highly flexible and supports various packet
formats. In transmit mode, the packet manager can be confi-
gured to add preamble, sync, and CRC words to the payload
data stored in the on-chip packet RAM. In receive mode, the
packet manager can detect and generate an interrupt to the
MCU upon receiving valid sync or CRC words, and store the
received data payload in the packet RAM. A total of 256 bytes of
transmit and receive packet RAM space is provided to decouple
the over-the-air data rate from the host MCU processing speed.
Thus, the ADF7242 packet manager eases the processing
burden on the host MCU and saves the overall system power
consumption.
The ADF7242 complies with the IEEE 802.15.4-2006 2.4 GHz
PHY requirements with a fixed data rate of 250 kbps and DSSS-
OQPSK modulation. With its support of GFSK/FSK/GMSK/MSK
modulation schemes, the IC can operate over a wide range of
data rates from 50 kbps to 2 Mbps and is, therefore, equally
suitable for proprietary applications in the areas of smart
metering, industrial control, home and building automation,
and consumer electronics. In addition, the agile frequency
synthesizer of the ADF7242, together with short turnaround
times, facilitates the implementation of FHSS systems.
The transmitter path of the ADF7242 is based on a direct
closed-loop VCO modulation scheme using a low noise
fractional-N RF frequency synthesizer. The automatically
calibrated VCO operates at twice the fundamental frequency to
reduce spurious emissions and avoid PA pulling effects. The
bandwidth of the RF frequency synthesizer is automatically
optimized for transmit and receive operations to achieve
optimum phase noise, modulation quality, and synthesizer
settling time performance. The transmitter output power is
programmable from −20 dBm to +4 dBm with automatic PA
ramping to meet transient spurious specifications. An
integrated biasing and control circuit is available in the IC to
significantly simplify the interface to external PAs.
In addition, for applications that require data streaming, a
synchronous bidirectional serial port (SPORT) provides bit-
level input/output data, and has been designed to directly inter-
face to a wide range of DSPs, such as ADSP-21xx, SHARC®,
TigerSHARC®, and Blackfin®. The SPORT interface can option-
ally be used for GFSK/FSK as well as IEEE 802.15.4-2006 modes.
The processor also permits the download and execution of a set
of firmware modules, which include IEEE 802.15.4 automatic
modes, such as node address filtering, as well as unslotted
CSMA/CA. Execution code for these firmware modules is
available from Analog Devices, Inc.
The receive path is based on a zero-IF architecture enabling very
high blocking resilience and selectivity performance, which are
critical performance metrics in interference dominated environ-
ments such as the 2.4 GHz band. In addition, the architecture
does not suffer from any degradation of blocker rejection in the
image channel, which is typically found in low IF receivers. In
GFSK/FSK modes, the receiver features a high speed automatic
frequency control (AFC) loop, which allows the frequency
synthesizer to find and correct any frequency errors in the
received packet.
To further optimize the system power consumption, the ADF7242
features an integrated low power 32 kHz RC wake-up oscillator,
which is calibrated from the 26 MHz crystal oscillator while the
transceiver is active. Alternatively, an integrated 32 kHz crystal
oscillator can be used as a wake-up timer for applications
requiring very accurate wake-up timing. A battery backed-up
RAM (BBRAM) is available on the IC where IEEE 802.15.4-
2006 network node addresses can be retained when the IC is in
the sleep state.
The ADF7242 also features a very flexible interrupt controller,
which provides MAC-level and PHY-level interrupts to the host
MCU. The IC is equipped with a SPI interface, which allows
burst-mode data transfer for high data throughput efficiency.
The IC also integrates a temperature sensor with digital read-
back and a battery monitor.
The IC can operate with a supply voltage between 1.8 V and 3.6 V
with very low power consumption in receive and transmit modes
while maintaining its excellent RF performance, making it espe-
cially suitable for battery-powered systems.
Rev. 0 | Page 4 of 108
ADF7242
4kB
PROGRAM
ROM
ADF7242
DAC
ADC
8-BIT
PROCESSOR
FSK
DEMOD
RFIO1P
2kB
PROGRAM
RAM
LNA1
RFIO1N
RFIO2P
RADIO
CONTROLLER
DSSS
DEMOD
256- BYTE
PACKET
RAM
LNA2
ADC
DAC
AGC
OCL
AFC
CDR
RFIO2N
PACKET
MANAGER
64-BYTE
BBRAM
256-BYTE
MCR
SDM
PFD
PRE-EMPHASIS
FSK MOD
DSSS MOD
PA
DIV2
DIVIDER
CS
FILTER
MOSI
SCLK
MISO
SPI
GAUSSIAN
Tx FILTER
CHARGE-
PUMP
LOOP FILTER
PABIAOP_ATB4
PAVSUP_ATB3
EXT PA
INTERFACE
WAKE-UP CTRL
RXEN_GP6
TXEN_GP5
EXT LNA/PA
ENABLE
GPIO
PA
RAMP
BATTERY TEMPERATURE
ANALOG
TEST
MONITOR
SENSOR
TIMER UNIT
TRCLK_CKO_GP3
DT_GP1
SPORT
26MHz
OSC
DR_GP0
32kHz
RC
OSC
32kHz
XTAL
OSC
IRQ1_GP4
RC
CAL
LDO1
LDO2
LDO3
LDO4
BIAS
IRQ
IRQ2_TRFS_GP2
CREGRF1, CREGVCO CREGSYNTH CREGDIG1, RBIAS XOSC26P XOSC26N
XOSC32KN_ATB2 XOSC32KP_GP7_ATB1
CREGRF2,
CREGRF3
CREGDIG2
Figure 2. Detailed Functional Block Diagram
Rev. 0 | Page 5 of 108
ADF7242
SPECIFICATIONS
VDD_BAT = 1.8 V to 3.6 V, GND = 0 V, TA = TMIN to TMAX, unless otherwise noted. Typical specifications are at VDD_BAT = 3.6 V,
TA = 25°C, fCHANNEL = 2450 MHz. All measurements are performed using the ADF7242 reference design, RFIO2 port, unless otherwise
noted.
GENERAL SPECIFICATIONS
Table 1.
Parameter
Min
Typ
Max
Unit
Test Conditions
GENERAL PARAMETERS
Voltage Supply Range
VDD_BAT Input
1.8
3.6
V
Frequency Range
Operating Temperature Range
Data Rate
2400
−40
2483.5 MHz
+85
°C
GFSK/FSK Mode
IEEE 802.15.4-2006 Mode
Resolution
50
2000
kbps
kbps
bps
250
100
Applies to FSK modes only
RF FREQUENCY SYNTHESIZER SPECIFICATIONS
Table 2.
Parameter
Min
Typ
10
3
Max
Unit
Test Conditions
CHANNEL FREQUENCY RESOLUTION
PHASE ERROR
kHz
Applies to GFSK/FSK modes
Degrees
Receive mode; any data rate, IEEE 802.15.4-2006 or
GFSK/FSK mode; integration bandwidth from 10 kHz
to 400 kHz
1.5
2
Degrees
Degrees
Degrees
μs
Transmit mode; IEEE 802.15.4-2006, 2 Mbps to
290 kbps, GFSK/FSK/GMSK/MSK mode; integration
bandwidth from 10 kHz to 1800 kHz
Transmit mode; 289.9 kbps to 184 kbps
GFSK/FSK/GMSK/MSK mode; integration bandwidth
from 10 kHz to 800 kHz
Transmit mode; 183.9 kbps to 50 kbps
GFSK/FSK/GMSK/MSK mode; integration bandwidth
from 10 kHz to 500 kHz
2.5
52
VCO CALIBRATION TIME
Applies to all modes
SYNTHESIZER SETTLING TIME
Frequency synthesizer settled to < 5 ppm of the
target frequency within this time following a VCO
calibration
53
80
39
35
μs
μs
μs
μs
Receive mode; any data rate, IEEE 802.15.4-2006 or
GFSK/FSK mode
Transmit mode; IEEE 802.15.4-2006, 2 Mbps to
289.6 kbps GFSK/FSK mode
Transmit mode; 289.7 kbps to 184 kbps GFSK/FSK
mode
Transmit mode; 183.9 kbps to 50 kbps GFSK/FSK
mode
PHASE NOISE
Receive mode; any data rate, IEEE 802.15.4-2006 or
GFSK/FSK mode
−135
−145
70
dBc/Hz
dBc/Hz
dBc
10 MHz frequency offset
≥50 MHz frequency offset
REFERENCE AND CLOCK-RELATED
SPURIOUS
Receive mode; IEEE 802.15.4-2006 or GFSK/FSK
mode; fCHANNEL = 2405 MHz, 2450 MHz, and 2480 MHz
Rev. 0 | Page 6 of 108
ADF7242
Parameter
Min
Typ
Max
Unit
Test Conditions
INTEGER BOUNDARY SPURS
60
dBc
Receive mode; IEEE 802.15.4-2006 or GFSK/FSK
mode; measured at 400 kHz offset from fCHANNEL
2405 MHz, 2418 MHz, 2431 MHz, 2444 MHz,
2457 MHz, 2470 MHz
=
CRYSTAL OSCILLATOR
Crystal Frequency
26
18
7
MHz
pF
pF
Parallel load resonant crystal
Maximum Parallel Load Capacitance
Minimum Parallel Load Capacitance
Maximum Crystal ESR
365.3
Ω
Guarantees maximum crystal frequency error of
0.2 ppm; 33 pF on XOSC26P and XOSC26N
Sleep-to-Idle Wake-Up Time
300
μs
15 pF load on XOSC26N and XOSC26P
TRANSMITTER SPECIFICATIONS
Table 3.
Parameter
Min
Typ
Max
Unit
Test Conditions
GENERAL TRANSMITTER SPECIFICATIONS
Maximum Transmit Power
Minimum Transmit Power
3
−25
4.8
dBm
dBm
dBm
Maximum Transmit Power (High Power
Mode)
Refer to Power Amplifier section for details on how
to enable this mode
Minimum Transmit Power(High Power
Mode)
Transmit Power Variation
−22
2
dBm
dB
Transmit power = 3 dBm, fCHANNEL = 2400 MHz to
2483.5 MHz, TA = −40°C to +85°C, VDD_BAT = 1.8 V
to 3.6 V
Transmit Power Control Resolution
Optimum PA Matching Impedance
2
dB
Ω
Transmit power = 3dBm
For maximum transmit power = 3 dBm
43.7 +
35.2j
Harmonics and Spurious Emissions
Compliance with ETSI EN 300 440
25 MHz to 30 MHz
−36
−36
−54
dBm
dBm
dBm
Unmodulated carrier, 10 kHz RBW1
Unmodulated carrier, 100 kHz RBW1
Unmodulated carrier, 100 kHz RBW1
30 MHz to 1 GHz
47 MHz to 74 MHz, 87.5 MHz to
118 MHz, 174 MHz to 230 MHz,
470 MHz to 862 MHz
Otherwise Above 1 GHz
Compliance with ETSI EN 300 328
1800 MHz to 1900 MHz
−30
dBm
Unmodulated carrier, 1 MHz RBW1
Unmodulated carrier
−47
−97
dBm
dBm/Hz
5150 MHz to 5300 MHz
Compliance with FCC CFR47, Part15
4.5 GHz to 5.15 GHz
7.25 GHz to 7.75 GHz
−41
−41
dBm
dBm
1 MHz RBW1
1 MHz RBW1
TRANSMIT PATH IEEE 802.15.4-2006 MODE
Transmit EVM
2
1
%
%
Measured using Rohde & Schwarz FSU vector
analyzer with Zigbee™ option
fCHANNEL = 2405 MHz to 2480 MHz, TA= −40°C to
+85°C, VDD_BAT = 1.8 V to 3.6 V
Transmit EVM Variation
Transmit PSD Mask
−56
2252
dBm
MHz
RBW = 100 kHz; |f – fCHANNEL| > 3.5 MHz
Transmit 20 dB Bandwidth
TRANSMIT PATH GFSK/FSK MODE
Frequency Deviation Resolution
Gaussian Filter BT
10
0.5
kHz
Gaussian filter available for 2000 kbps, 1000 kbps,
500 kbps, 250 kbps, 125 kbps and 62.5 kbps only
Rev. 0 | Page 7 of 108
ADF7242
Parameter
Min
Typ
Max
Unit
Test Conditions
Transmit Modulation Phase Error
7
Degrees
2 Mbps (fDEV = 500 kHz) GFSK SPORT mode,
transmitter output power = 3 dBm
6.5
4.5
6
Degrees
Degrees
Degrees
Degrees
dB
1 Mbps (fDEV = 250 kHz) GFSK SPORT mode,
transmitter output power = 3 dBm
500 kbps (fDEV = 250 kHz) GFSK SPORT mode,
transmitter output power = 3 dBm
250 kbps (fDEV = 130 kHz) GFSK SPORT mode,
transmitter output power = 3 dBm
125 kbps (fDEV = 60 kHz) FSK SPORT mode,
transmitter output power = 3 dBm
4
Transmit Modulation Error Rate (MER)
24
2 Mbps GFSK SPORT mode, transmitter output
power = 3dBm; measured as the standard deviation
from 500 kHz frequency deviation
24
24
24
22
dB
dB
dB
dB
1 Mbps GFSK SPORT mode, transmitter output
power = 3 dBm; measured as the standard deviation
from 250 kHz frequency deviation
500 kbps GFSK SPORT mode, transmitter output
power = 3dBm; measured as the standard deviation
from 250 kHz frequency deviation
250 kbps GFSK SPORT mode, transmitter output
power = 3 dBm; measured as the standard deviation
from 130 kHz frequency deviation
125 kbps FSK SPORT mode, transmitter output
power = 3 dBm; measured as the standard deviation
from 60 kHz frequency deviation
Transmit 20 dB Bandwidth
2 Mbps GFSK SPORT Mode
1 Mbps GFSK SPORT Mode
500 kbps GFSK SPORT Mode
250 kbps GFSK SPORT Mode
125 kbps GFSK SPORT Mode
62.5 kbps FSK SPORT Mode
Transmit Adjacent Channel Power
First Channel
2520
1250
985
520
302
kHz
kHz
kHz
kHz
kHz
kHz
2 Mbps (fDEV = 500 kHz) GFSK SPORT mode
1 Mbps (fDEV = 250 kHz) GFSK SPORT mode
500 kbps (fDEV = 250 kHz) GFSK SPORT mode
250 kbps (fDEV = 130 kHz) GFSK SPORT mode
125 kbps (fDEV = 60 kHz) FSK SPORT mode
62.5 kbps (fDEV = 60 kHz) FSK SPORT mode
226
−53.5
−54.5
dBm
dBm
2 Mbps GFSK SPORT mode, 5 MHz channel spacing
2.2 MHz channel bandwidth, transmitter output
power = 3 dBm
Second Channel
First Channel
Second Channel
−27
−51.5
dBm
dBm
250 kbps FSK SPORT mode, 300 kHz channel spacing
250 kHz channel bandwidth, transmitter output
power = 3 dBm
1 RBW = resolution bandwidth.
RECEIVER SPECIFICATIONS
Table 4.
Parameter
Min
Typ
Max
Unit
Test Conditions
GENERAL RECEIVER SPECIFICATIONS
RF Front-End LNA and Mixer IIP3
−13.6
−12.6
dBm
dBm
At maximum gain, fBLOCKER1 = 5 MHz,
f
BLOCKER2 = 10.1 MHz, PRF,IN = −35 dBm
At maximum gain, fBLOCKER1 = 20 MHz,
fBLOCKER2 = 40.1 MHz,
P
RF,IN = −35 dBm
At maximum gain, fBLOCKER1 = 40 MHz,
BLOCKER2 = 80.1 MHz,
PRF,IN = −35 dBm
−10.5
dBm
f
Rev. 0 | Page 8 of 108
ADF7242
Parameter
Min
Typ
Max
Unit
Test Conditions
RF Front-End LNA and Mixer IIP2
24.7
dBm
At maximum gain, fBLOCKER1 = 5 MHz,
f
BLOCKER2 = 5.5 MHz, PRF,IN = −50 dBm
RF Front-End LNA and Mixer 1 dB
Compression Point
−20.5
dBm
At maximum gain
Receiver LO Level at RFIO2 Port
LNA Input Impedance at RFIO1 Port
−100
50.2 −
52.2j
dBm
Ω
IEEE 802.15.4 packet mode
Measured in RX state
LNA Input Impedance at RFIO2 Port
74.3 −
10.7j
Ω
Measured in RX state
Receive Spurious Emissions
Compliant with EN 300 440
30 MHz to 1000 MHz
−57
−47
dBm
dBm
1 GHz to 12.75 GHz
RECEIVE PATH IEEE 802.15.4-2006 MODE
Sensitivity (Prf,in,min, 802154)
−95
−15
dBm
dBm
1% PER with PSDU length of 20 bytes according to
the IEEE 802.15.4-2006 standard
1% PER with PSDU length of 20 bytes
Saturation Level
CW Blocker Rejection
5 MHz
55
60
63
64
dB
dB
dB
dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
10 MHz
20 MHz
30 MHz
Modulated Blocker Rejection
5 MHz
48
61
62.5
65
65
dB
dB
dB
dB
dB
dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
PRF,IN = PRF,IN,MIN, 802154 + 3 dB
Prf,IN = Prf,IN,MIN + 10 dB Modulated Blocker
10 MHz
15 MHz
20 MHz
30 MHz
Co-Channel Rejection
Out-of Band Blocker Rejection
−5 MHz
−6
−34.2
−30.7
−29.7
−25.7
−24.2
−33.4
−29.9
−28.2
−23.7
−29.9
dBm
dBm
dBm
dBm
dBm
dBm
dBm
dBm
dBm
dBm
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2405 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
−10 MHz
−20 MHz
−30 MHz
−60 MHz
+5 MHz
f
CHANNEL = 2405 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2405 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2405 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
f
CHANNEL = 2405 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2480 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2480 MHz
+10 MHz
+20 MHz
+30 MHz
+60 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
f
CHANNEL = 2480 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2480 MHz
PRF,IN = PRF,IN,MIN, 802154 + 3 dB, measured at
fCHANNEL = 2480 MHz
Receiver Channel Bandwidth
Frequency Error Tolerance
2252
kHz
Two-sided bandwidth; cascaded analog and digital
channel filtering
−80
+80
ppm
PRF,IN = PRF,IN,MIN + 3 dB
Rev. 0 | Page 9 of 108
ADF7242
Parameter
Min
Typ
Max
Unit
Test Conditions
RSSI
Measured using IEEE 802.15.4-2006 packet mode
Dynamic range
85
dB
Accuracy
3
dB
Averaging Time
128
−95
μs
dBm
Minimum Sensitivity
RECEIVE PATH GFSK MODE
Sensitivity 1 % PER
PRF,IN,MIN 2 Mbps
−84.5
−87.5
−92
−92
−94
−95
−96
−96
dBm
dBm
dBm
dBm
dBm
dBm
dBm
dBm
2000 kbps (fDEV = 500 kHz) GFSK packet mode
1000 kbps (fDEV = 250 kHz) GFSK packet mode
500 kbps (fDEV = 250 kHz) GFSK packet mode
250 kbps (fDEV = 130 kHz) GFSK packet mode
125 kbps (fDEV = 60 kHz) FSK packet mode
100 kbps (fDEV = 30 kHz) FSK packet mode
62.5 kbps (fDEV = 60 kHz) FSK packet mode
50 kbps (fDEV = 30 kHz) FSK packet mode
PRF,IN,MIN 1 Mbps
PRF,IN,MIN 500 kbps
PRF,IN,MIN 250 kbps
PRF,IN,MIN 125 kbps
PRF,IN,MIN 100 kbps
PRF,IN,MIN 62.5 kbps
PRF,IN,MIN 50 kbps
Sensitivity 0.1% BER
PRF,IN,MIN 2 Mbps
PRF,IN,MIN 1 Mbps
PRF,IN,MIN 500 kbps
PRF,IN,MIN 250 kbps
PRF,IN,MIN 125 kbps
PRF,IN,MIN 62.5 kbps
PRF,IN,MIN 50 kbps
−87.5
−90
−93
−93
−93
−96
−96
11
9
7
7
7
7
dBm
dBm
dBm
dBm
dBm
dBm
dBm
Bytes
Bytes
Bytes
Bytes
Bytes
Bytes
Bytes
Bytes
2000 kbps (fDEV = 500 kHz) GFSK SPORT mode
1000 kbps (fDEV = 250 kHz) GFSK SPORT mode
500 kbps (fDEV = 250 kHz) GFSK SPORT mode
250 kbps (fDEV = 130 kHz) GFSK SPORT mode
125 kbps (fDEV = 60 kHz) FSK SPORT mode
62.5 kbps (fDEV = 6 0kHz) FSK SPORT mode
50 kbps (fDEV = 30 kHz) FSK SPORT mode
2000 kbps (fDEV = 50 0kHz) GFSK packet mode
1000 kbps (fDEV = -250 kHz) GFSK packet mode
500 kbps (fDEV = 250 kHz) GFSK packet mode
250 kbps (fDEV = -130 kHz) GFSK packet mode
125 kbps (fDEV = 60 kHz) FSK packet mode
100 kbps (fDEV = -30 kHz) FSK packet mode
62.5 kbps (fDEV = -60 kHz) FSK packet mode
50 kbps (fDEV = 30 kHz) FSK packet mode
Minimum Preamble Length
6
6
Saturation Level
−15
dBm
All GFSK/FSK modes, packet and SPORT modes, 1%
PER and 0.1% BER
CW Blocking Rejection (2000 kbps (fDEV
500 kHz) GFSK Packet Mode)
=
PRF,IN = PRF,IN,MIN, 2 Mbps + 3 dB
5 MHz
51
56
56.5
60.5
dB
dB
dB
dB
10 MHz
20 MHz
30 MHz
Modulated Blocking Rejection (2000 kbps
(fDEV = 500 kHz) GFSK Packet Mode)
PRF,IN = PRF,IN,MIN, 2 Mbps + 3 dB
5 MHz
48
53
58
60
dB
dB
dB
dB
10 MHz
20 MHz
30 MHz
CW Blocker Rejection (125 kbps (fDEV
60 kHz) FSK Packet Mode)
=
PRF,IN = PRF,IN,MIN, 125 kbps + 3 dB
2 MHz
5 MHz
12 MHz
20 MHz
32 MHz
54.5
62
64
69
70.5
dB
dB
dB
dB
dB
Rev. 0 | Page 10 of 108
ADF7242
Parameter
Min
Typ
Max
Unit
Test Conditions
Modulated Blocking Rejection
(2000 kbps (fDEV = 500 kHz) GFSK
Packet Mode)
PRF,IN = PRF,IN,MIN, 125 kbps + 3 dB
2 MHz
5 MHz
12 MHz
20 MHz
32 MHz
52.5
60
64.5
68.5
71
dB
dB
dB
dB
dB
dB
Co-Channel Rejection
−13
2000 kbps (fDEV = 500 kHz) GFSK packet mode,
PRF,IN = PRF,IN,MIN, 2 Mbps + 10 dB, modulated blocker
−9
dB
250 kbps (fDEV = 130 kHz) GFSK packet mode,
PRF,IN = PRF,IN,MIN, 250 kbps + 10 dB, modulated blocker
Receiver Channel Bandwidth
Minimum Channel 3 dB Bandwidth
Analog Filter
Analog and Digital Filter Cascade
Maximum Channel 3 dB Bandwidth
1110
520
2252
kHz
kHz
kHz
Two-sided bandwidth
Two-sided bandwidth
Two-sided bandwidth
Frequency Error Tolerance, 2000 kbps
(fDEV = 500 kHz) GFSK Packet Mode
AFC Off
AFC On
55
165
kHz
kHz
AFC pull-in range = 80 kHz
AFC pull-in range = 80 kHz
Frequency Error Tolerance, 500 kbps
(fDEV = 250 kHz) FSK Packet Mode
AFC Off
AFC On
90
190
kHz
kHz
RSSI, 2000 kbps (fDEV = 500 kHz) GFSK
Mode
Accuracy
3
dBm
dBm
dBm
Minimum Sensitivity, Packet Mode
Minimum Sensitivity, SPORT Mode
RSSI, 500 kbps (fDEV = 250 kHz) GFSK Mode
Accuracy
−84.5
−87.5
SPORT mode with no preamble or SWD detection
SPORT mode with no preamble or SWD detection
3
−92
−93
dBm
dBm
dBm
Minimum Sensitivity, Packet Mode
Minimum Sensitivity, SPORT Mode
AUXILIARY SPECIFICATIONS
Table 5.
Parameter
Min
Typ
Max
Unit
Test Conditions
32 kHz RC OSCILLATOR
Frequency
32.768
1
kHz
%
After calibration
After calibration at 25°C
Frequency Accuracy
Frequency Drift
Temperature Coefficient
Voltage Coefficient
Calibration Time
32 kHz CRYSTAL OSCILLATOR
Frequency
0.14
4
1
%/°C
%/V
ms
32.768
319.8
2000
kHz
kΩ
ms
Maximum ESR
Start-Up Time
10 pF on XOSC32KP and XOSC32KN
12.5pF load capacitors on XOSC32KP and
XOSC32KN
WAKE-UP TIMER
Prescaler Tick Period
Wake-Up Period
0.0305
61 × 10−6
20,000
ms
1.31 × 105 sec
Rev. 0 | Page 11 of 108
ADF7242
Parameter
TEMPERATURE SENSOR
Range
Resolution
Accuracy
Min
Typ
Max
Unit
Test Conditions
−40
+85
°C
°C
°C
4.7
6.4
Average of 1000 ADC readbacks, after
using linear fitting, with correction at
known temperature
BATTERY MONITOR
Trigger Voltage
1.7
3.6
V
Trigger Voltage Step Size
Start-Up Time
Current Consumption
62
5
30
mV
μs
μA
EXTERNAL PA INTERFACE
RON, PAVSUP_ATB3 to VDD_BAT
ROFF, PAVSUP_ATB3 to GND
ROFF, PABIASOP_ATB4 to GND
PABIASOP_ATB4 Source Current, Maximum
PABIASOP_ATB4 Sink Current, Minimum
PABIASOP_ATB4 Current Control Resolution
PABIASOP_ATB4 Compliance Voltage
PABIASOP_ATB4 Compliance Voltage
Servo Loop Bias Current
5
10
10
80
−80
6
150
3.45
22
Ω
extpa_bias_mode = 0, 1, 2, 5, 6
extpa_bias_mode = 3, 4, power-down
extpa_bias_mode = 0, power-down
expta_bias_mode = 1, 3
extpa_bias_mode = 2, 4
extpa_bias_mode = 1, 2, 3, 4, 5
extpa_bias_mode = 2, 4
extpa_bias_mode = 1, 3
extpa_bias_mode = 5, 6
extpa_bias_mode = 5, 6
MΩ
MΩ
μA
μA
Bits
mV
V
mA
mA
Servo Loop Bias Current Control Step
0.349
CURRENT CONSUMPTION SPECIFICATIONS
Table 6.
Parameter
Min
Typ
Max
Unit
Test Conditions
CURRENT CONSUMPTION
TX Mode Current Consumption
−20 dBm
16.5
17.4
19.6
21.5
25
1.8
10
19
mA
mA
mA
mA
mA
mA
mA
mA
mA
μA
IEEE 802.15.4-2006 continuous packet transmission mode
IEEE 802.15.4-2006 continuous packet transmission mode
IEEE 802.15.4-2006 continuous packet transmission mode
IEEE 802.15.4-2006 continuous packet transmission mode
IEEE 802.15.4-2006 continuous packet transmission mode
XTO26M + digital active
−10 dBm
0 dBm
+3 dBm
+4 dBm
Idle Mode
PHY_RDY Mode
RX Mode Current Consumption
MEAS State
SLEEP_BBRAM
SLEEP_BBRAM_RCO
IEEE 802.15.4-2006 packet mode
BBRAM contents retained
32 kHz RC oscillator running, some BBRAM contents
retained, wake-up time enabled
3
0.3
1
μA
SLEEP_BBRAM_XTO
1.7
μA
32 kHz crystal oscillator running, some BBRAM contents
retained, wake-up time enabled
Rev. 0 | Page 12 of 108
ADF7242
TIMING AND DIGITAL SPECIFICATIONS
Table 7. Logic Levels
Parameter
Min
Typ
Max
Unit
Test Conditions
LOGIC INPUTS
Input High Voltage, VINH
Input Low Voltage, VINL
Input Current, IINH/IINL
Input Capacitance, CIN
LOGIC OUTPUTS
0.7 × VDD_BAT
V
V
μA
pF
0.2 × VDD
1
10
Output High Voltage, VOH
Output Low Voltage, VOL
Output Rise/Fall
VDD_BAT − 0.4
V
V
ns
pF
IOH = 500 μA
IOL = 500 μA
0.4
5
7
Output Load
Table 8. GPIOs
Parameter
Min
Typ
Max
Unit
Test Conditions
GPIO OUTPUTS
Output Drive Level
Output Drive Level
5
5
mA
mA
All GPIOs in logic high state
All GPIOs in logic low state
Table 9. SPI Interface Timing
Parameter Min
Typ
Max
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
μs
ns
ns
ms
Description
t1
15
CS falling edge to MISO setup time (TRX active)
CS to SCLK setup time
t2
40
40
40
80
t3
t4
t5
SCLK high time
SCLK low time
SCLK period
SCLK falling edge to MISO delay
MOSI to SCLK rising edge setup time
MOSI to SCLK rising edge hold time
SCLK to CS hold time
t6
10
t7
5
t8
5
t9
40
10
270
t10
t11
t12
t13
t14
t15, t16
CS high to SCLK wait time
CS high time
300
400
20
20
CS low to MISO high wake-up time, 26 MHz crystal with 10 pF load capacitance, TA = 25°C
SCLK rise time
SCLK fall time
2
CS high time on wake-up after RC_RESET or RC_SLEEP command (see Figure 5 and
Figure 70) 26 MHz crystal with 10 pF load
Rev. 0 | Page 13 of 108
ADF7242
Table 10. IEEE 802.15.4 State Transition Timing
Parameter
Min
Typ
142
13.5
192
192
140
140
192
192
23
192
14.5
5.5
30.5
19
Max
Unit
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
Test Conditions
Idle to PHY_RDY State
PHY_RDY to Idle State
PHY_RDY or TX to RX State (Different Channel)
PHY_RDY or RX to TX State (Different Channel)
PHY_RDY or TX to RX State (Same Channel)
RX or PHY_RDY to TX State (Same Channel)
RX Channel Change
TX Channel Change
TX to PHY_RDY State
PHY_RDY to CCA State
CCA to PHY_RDY State
RX to Idle State
TX to Idle State
Idle to MEAS State
MEAS to Idle State
CCA to Idle State
RX to CCA State
CCA to RX State
VCO calibration performed
VCO calibration performed
VCO calibration skipped
VCO calibration skipped
VCO calibration performed
VCO calibration performed
6
14.5
18
205
Table 11. GFSK/FSK State Transition Timing
Parameter
Min
Typ
180
13.5
Max
Unit
μs
μs
Test Conditions
Idle to PHY_RDY State
PHY_RDY to Idle State
PHY_RDY or TX to RX State (Different Channel)
PHY_RDY or RX to TX State (Different Channel)
PHY_RDY or RX to TX State (Different Channel)
664
μs
μs
μs
VCO calibration performed
VCO calibration performed
VCO calibration performed,
mac_delay_ext1= 472 μs
192
664
PHY_RDY or TX to RX State (Same Channel)
RX or PHY_RDY to TX State (Same Channel)
RX or PHY_RDY to TX State (Same Channel)
612
140
664
μs
μs
μs
VCO calibration skipped
VCO calibration skipped
VCO calibration performed,
mac_delay_ext1 = 472 μs
RX Channel Change
TX Channel Change
TX Channel Change
664
192
664
μs
μs
μs
VCO calibration performed
VCO calibration performed
VCO calibration performed,
mac_delay_ext1 = 472 μs
TX to PHY_RDY State
PHY_RDY to CCA State
CCA to PHY_RDY State
RX to Idle State
23
μs
μs
μs
μs
μs
μs
μs
μs
μs
μs
192
14.5
18.5
30.5
19
6
14.5
18
TX to Idle State
Idle to MEAS State
MEAS to Idle State
CCA to Idle State
RX to CCA State
CCA to RX State
205
1 mac_delay_ext setting applies to both RX and TX states. The default setting is 0 μs.
Rev. 0 | Page 14 of 108
ADF7242
Table 12. Timing IEEE 802.15.4-2006 SPORT Mode
Parameter Min
Typ
Max
Unit
μs
μs
μs
μs
Test Conditions/Comments
t21
t22
t23
t24
18
SFD detect to TRCLK_CLKO_GP3 (data bit clock) active delay
TRCLK_CKO_GP3 bit period
DR_GP0 to TRCLK_CKO_GP3 falling edge setup time
TRCLK_CKO_GP3 symbol burst period
2
0.51
16
Table 13. MAC Timing
Parameter Min
Typ
Max
Unit
μs
μs
Test Conditions/Comments
t26
t27
38
Time from frame received to rx_pkt_rcvd interrupt generation
Time allowed, from issuing a RC_TX command, to update
Register delaycfg2, Bit mac_delay_ext (0x10B[7:0])
Time allowed, from issuing a RC_TX command, to cancel the RC_TX
command
150
150
t28
μs
tRX_MAC_DELAY
192
μs
μs
IEEE 802.15.4 mode as defined by the standard
GFSK/FSK mode as required by state transition timing
664
Table 14. Timing GFSK SPORT Mode
Parameter Min
Typ
Max
Unit
Test Conditions/Comments
t29
14
μs
ns
ns
RC_PHY_RDY to TRCLK_CKO_GP3 (data clock) off
DR_GP0 to TRCLK_CKO_GP3 active edge hold time
DR_GP0 to TRCLK_CKO_GP3 active edge setup time
TRCLK_CLKO_GP3 clock period
DT_GP1 to TRCLK_CKO_GP3 sampling edge setup time
DT_GP1 to TRCLK_CKO_GP3 sampling edge hold time
PA nominal power to TRCLK_CKO_GP3 activity/entry into TX state
RC_PHY_RDY to TRCLK_CLKO_GP3 off
t30
t31
t32
t33
t34
t35
t36
t37
t38
t39
t40
t41
t42
tSYM/2 − 30
tSYM/2 − 30
tSYM
20
20
1.3
ns
ns
μs
μs
μs
ns
μs
μs
us
μs
6.2
14
10
RC_PHY_RDY to PA power shutdown
tSYM/2 − 60
Sync_word_length × tSYM
tSYM/2
IRQ2_TRFS_GP2 rising edge to TRCLK_CKO_GP3 active edge delay
DR_GP0 activity to end of sync word delay
Sync word detect to IRQ2_TRFS_GP2 high
TRCLK_CKO_GP3 active to valid data
RC_RX command to TRCLK_CKO_GP3 activity delay (calibrations
performed)
5 × tSYM
105
Sync_word_length × tSYM
TIMING DIAGRAMS
SPI Interface Timing Diagram
CS
t11
t2
t3 t4
t5
t9 t10
SCLK
MISO
t1
t6
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
BIT 7
BIT 0
X
BIT 7
t8
t7
MOSI
7
6
5
4
3
2
1
0
7
7
Figure 3. SPI Interface Timing
Additional description and timing diagrams are available in the Serial Peripheral interface section.
Rev. 0 | Page 15 of 108
ADF7242
Sleep-to-Idle SPI Timing
CS
t9
SCLK
MISO
7
6
5
4
3
2
1
0
t12
t6
t1
X
Figure 4. Sleep-to-Idle State Timing
t16
CS
RC_RESET OR
RC_SLEEP
SPI COMMAND
TO ADF7242
IDLE, PHY_RDY, RX
SLEEP
IDLE
DEVICE STATUS
Figure 5. Wake-Up After an RC_RESET or RC_SLEEP Command
MAC Delay Timing Diagram
PACKET
TRANSMITTED
FRAME IN TX_BUFFER
PACKET
RECEIVED
VALID IEEE802.15.4-2006 FRAME
PHY_RDY
RC_STATUS
RX
TX
tx_mac_delay +
mac_delay_ext
t26
t27,t28
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src1, FIELD rx_pkt_rcvd
REGISTER irq_src1, FIELD tx_pkt_sent
Figure 6. IEEE 802.15.4 MAC Timing
Rev. 0 | Page 16 of 108
ADF7242
IEEE 802.15.4 RX SPORT Mode Timing Diagrams
Table 15. IEEE 802.15.4 RX SPORT Modes Configurations
Register rc_cfg, Field rc_mode
(0x13E[7:0])
Register gp_cfg, Field gpio_config
(0x32C[7:0])
Functionality
2
0
1
7
Bit clock and data available (see Figure 7)
Symbol clock and data available (see Figure 8)
RC_RX
RC_PHY_RDY
COMMAND
PREVIOUS STATE
RC_STATUS
RX
PHY_RDY
t29
tRX_MAC_DELAY
PREAMBLE SFD
PHR
t21
PSDU
t21
TRCLK_CKO_GP3
DR_GP0
t24
.....
DATA
INVALID
.....
.....
.....
TRCLK_CKO_GP3
DR_GP0 .....
t23
t22
Figure 7. IEEE 802.15.4 RX SPORT Mode: Bit Clock and Data Available
RC_RX
RC_PHY_RDY
COMMAND
PREVIOUS STATE
RC_STATUS
RX
PHY_RDY
t29
tRX_MAC_DELAY
PREAMBLE SFD
PHR
t21
PSDU
t26
t21
TRCLK_CKO_GP3
1
SYMBOL
GP6, GP5, GP1, GP0
[3:0]
[3:0]
[3:0]
[3:0]
[3:0] [3:0]
[3:0]
[3:0]
1
GP6 = RXEN_GP6
GP5 = TXEN_GP5
GP1 = DT_GP1
GP0 = DR_GP0
Figure 8. IEEE 802.15.4 RX SPORT Mode: Symbol Clock Output
Rev. 0 | Page 17 of 108
ADF7242
IEEE 802.15.4 TX SPORT MODE TIMING DIAGRAMS
Table 16. IEE 802.15.4 TX SPORT Mode Configurations
Register rc_cfg, Field rc_mode
(0x13E[7:0])
Register gp_cfg, Field gpio_config
(0x32C[7:0])
Functionality
3
1 or 4
Transmission starts after PA ramp up (see Figure 9)
gpio_config = 1: data clocked in on rising edge of clock
gpio_config = 4: data clocked in on falling edge of clock
RC_TX
RC_PHY_RDY
PHY_RDY
t37
PHY_RDY
TX
RC STATE
PA POWER
t35
PACKET
COMPONENT
PREAMBLE
SFD
PHR
PSDU
t36
TRCLK_CKO_GP3
DT_GP1
.....
PACKET DATA
.....
REGISTER gp_cfg, FIELD gpio_config = 1
DATA CLOCKED IN ON RISING EDGE
t32
REGISTER gp_cfg, FIELD gpio_config = 4
DATA CLOCKED IN ON FALLING EDGE
t32
TRCLK_CKO_GP3
TRCLK_CKO_GP3
DT_GP1 SAMPLE
DT_GP1 SAMPLE
DT_GP1
DT_GP1
t33
t34
Figure 9. IEEE 802.15.4-2006 TX SPORT Mode
t33
t34
Refer to the SPORT Interface section for further details.
GFSK/FSK RX SPORT MODE TIMING DIAGRAMS
Table 17. GFSK/FSK RX SPORT Mode Configurations
Register rc_cfg, Field rc_mode
(0x13E[7:0])
Register gp_cfg, Field gpio_config
(0x32C[7:0])
Functionality
3
3
3
1 or 4
TRCLK and data pins active in RX, without gating by frame
detection (see Figure 10)
gpio_config = 1: data clocked out on falling edge/rising edge
gpio_config = 4: data clocked out on rising edge/rising edge
2 or 5
3 or 6
TRCLK and Data pins activity gated by preamble detection (see
Figure 11)
gpio_config = 2: data clocked out on falling edge/rising edge
gpio_config = 5: data clocked out on rising edge/rising edge
TRCLK and data pins activity gated by synchronization word
detection (see Figure 12)
gpio_config = 3: data clocked out on falling edge/rising edge
gpio_config = 6: data clocked out on rising edge/rising edge
Rev. 0 | Page 18 of 108
ADF7242
RC_RX
RC_PHY_RDY
COMMAND
RC_STATUS
PREVIOUS STATE
tRX_MAC_DELAY
t42
RX
PHY_RDY
t29
PACKET
COMPONENT
SYNC
WORD
POST-
AMBLE
PREAMBLE
PAYLOAD
IRQ2_TRFS_GP2
TRCLK_CKO_GP3
DR_GP0
.....
.....
PACKET DATA
DATA INVALID
REGISTER gp_cfg, FIELD gpio_config = 1
DATA CLOCKED OUT ON FALLING EDGE
REGISTER gp_cfg, FIELD gpio_config = 4
DATA CLOCKED OUT ON RISING EDGE
IRQ2_TRFS_GP2
IRQ2_TRFS_GP2
t32
t32
TRCLK_CKO_GP3
DR_GP0
TRCLK_CKO_GP3
t31
t31
t30
t30
DR_GP0
Figure 10. GFSK/FSK RX SPORT Mode: CLK and Data Pins Active in RX, Without Gating by Frame Detection
RC_RX
RC_PHY_RDY
COMMAND
RC_STATUS
PREVIOUS STATE
tRX_MAC_DELAY
RX
PHY_RDY
t29
PACKET
COMPONENT
SYNC
WORD
POST-
AMBLE
PREAMBLE
PAYLOAD
t40
IRQ2_TRFS_GP2
t41
TRCLK_CKO_GP3
DR_GP0
.....
.....
t39
PACKET DATA
DATA INVALID
REGISTER gp_cfg, FIELD gpio_config = 2
DATA CLOCKED OUT ON FALLING EDGE
REGISTER gp_cfg, FIELD gpio_config = 5
DATA CLOCKED OUT ON RISING EDGE
IRQ2_TRFS_GP2
IRQ2_TRFS_GP2
t38
t32
t38
t32
TRCLK_CKO_GP3
DR_GP0
TRCLK_CKO_GP3
DR_GP0
t31
t31
t30
t30
Figure 11. GFSK/FSK RX SPORT Mode: SCLK and Data Pin Activity Gated By Preamble Detection
Rev. 0 | Page 19 of 108
ADF7242
RC_RX
RC_PHY_RDY
COMMAND
RC_STATUS
PREVIOUS STATE
tRX_MAC_DELAY
RX
PHY_RDY
t29
SYNC
WORD
POST-
AMBLE
PACKET
COMPONENT
PREAMBLE
PAYLOAD
IRQ2_TRFS_GP2
t40
TRCLK_CKO_GP3
DR_GP0
.....
t39
PACKET DATA
.....
DATA INVALID
REGISTER gp_cfg, FIELD gpio_config = 3
DATA CLOCKED OUT ON FALLING EDGE
REGISTER gp_cfg, FIELD gpio_config = 6
DATA CLOCKED OUT ON RISING EDGE
IRQ2_TRFS_GP2
IRQ2_TRFS_GP2
t38
t38
t32
t32
TRCLK_CKO_GP3
DR_GP0
TRCLK_CKO_GP3
DR_GP0
t31
t31
t30
t30
Figure 12. GFSK/FSK RX SPORT Mode: SCLK and Data Pins Activity Gated By Synchronization Word Detection
GFSK/FSK TX SPORT Mode Timing Diagrams
Table 18. GFSK/FSK TX SPORT Mode Configurations
Register rc_cfg, Field rc_mode
(0x13E[7:0])
Register gp_cfg, Field gpio_config
(0x32C[7:0])
Functionality
3
1 or 4
Transmission starts after PA ramp up (see Figure 13)
gpio_config = 1: data clocked in on rising edge of clock
gpio_config = 4: data clocked in on falling edge of clock
Rev. 0 | Page 20 of 108
ADF7242
RC_TX
RC_PHY_RDY
PHY_RDY
TX
PHY_RDY
t37
RC STATE
PA POWER
t35
SYNC
WORD
POST-
AMBLE
PACKET
COMPONENT
PSDU
PREAMBLE
t36
TRCLK_CKO_GP3
DT_GP1
.....
PACKET DATA
.....
REGISTER gp_cfg, FIELD gpio_config = 1
DATA CLOCKED IN ON RISING EDGE
t32
REGISTER gp_cfg, FIELD gpio_config = 4
DATA CLOCKED IN ON FALLING EDGE
t32
TRCLK_CKO_GP3
TRCLK_CKO_GP3
DT_GP1 SAMPLE
DT_GP1 SAMPLE
DT_GP1
DT_GP1
t33
t34
Figure 13. GFSK/FSK TX SPORT Mode
t33
t34
Refer to the SPORT Interface section for further details.
Rev. 0 | Page 21 of 108
ADF7242
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
The exposed paddle of the LFCSP package should be connected
to ground.
Table 19.
This device is a high performance RF integrated circuit with an
ESD rating of <2 kV, and it is ESD sensitive. Proper precautions
should be taken for handling and assembly.
Parameter
Rating
VDD_BAT to GND
−0.3 V to +3.9 V
Operating Temperature Range
Industrial
Storage Temperature Range
Maximum Junction Temperature
LFCSP θJA Thermal Impedance
Reflow Soldering
−40°C to +85°C
−65°C to +125°C
150°C
ESD CAUTION
26°C/W
Peak Temperature
Time at Peak Temperature
260°C
40 sec
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Rev. 0 | Page 22 of 108
ADF7242
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
CREGRF1
RBIAS
1
2
24 CS
23
MOSI
3
4
5
6
7
8
22 SCLK
21 MISO
CREGRF2
RFIO1P
RFIO1N
RFIO2P
RFIO2N
CREGRF3
ADF7242
TOP VIEW
(Not to Scale)
20
19
IRQ1_GP4
TRCLK_CKO_GP3
18 IRQ2_TRFS_GP2
17 DT_GP1
NOTES
1. THE EXPOSED PADDLE MUST BE CONNECTED
TO GROUND.
Figure 14. Pin Configuration
Table 20. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
CREGRF1
Regulated Supply Terminal for RF Section. Connect a 220 nF decoupling capacitor from this pin to
GND.
2
RBIAS
Bias Resistor 27 kΩ to Ground.
3
4
5
6
7
8
9
10
11
12
CREGRF2
RFIO1P
RFIO1N
RFIO2P
RFIO2N
CREGRF3
CREGVCO
VCOGUARD
CREGSYNTH
XOSC26P
Regulated Supply for RF Section. Connect a 100 pF decoupling capacitor to ground.
Differential RF Input Port 1 (Positive Terminal). A 10 nF coupling capacitor is required.
Differential RF Input Port 1 (Negative Terminal). A 10 nF coupling capacitor is required.
Differential RF Input/Output Port 2 (Positive Terminal). A 10 nF coupling capacitor required.
Differential RF Input/Output Port 2 (Negative Terminal). A 10 nF coupling capacitor required.
Regulated Supply for RF Section. Connect a 100 pF decoupling capacitor from this pin to GND.
Regulated Supply for VCO Section. Connect a 220 nF decoupling capacitor from this pin to GND.
Guard Trench for VCO Section. Connect to Pin 9 (CREGVCO).
Regulated Supply for PLL Section. Connect a 220 nF decoupling capacitor from this pin to GND.
Terminal 1 of External Crystal and Loading Capacitor. This pin is no connect (NC) when an external
oscillator is used.
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
XOSC26N
DGUARD
CREGDIG2
DR_GP0
Terminal 2 of External Crystal and Loading Capacitor. Input for external oscillator.
Guard Trench for Digital Section. Connect to Pin 15 (CREGDIG2).
Regulated Supply for Digital Section. Connect a 220 nF decoupling capacitor to ground.
SPORT Receive Data Output/General-Purpose IO Port.
SPORT Transmit Data Input/General-Purpose IO Port.
Interrupt Request Output 2/Symbol Clock IEEE 802.15.4-2006 Mode/General-Purpose IO Port.
SPORT Clock Output/General-Purpose IO Port.
Interrupt Request Output1/General-Purpose IO Port.
SPI Interface Serial Data Output.
SPI Interface Data Clock Input.
SPI Interface Serial Data Input.
DT_GP1
IRQ2_TRFS_GP2
TRCLK_CKO_GP3
IRQ1_GP4
MISO
SCLK
MOSI
CS
SPI Interface Chip Select Input (and Wake-Up Signal).
TXEN_GP5
RXEN_GP6
CREGDIG1
XOSC32KP_GP7_ATB1
External PA Enable Signal/General-Purpose IO Port.
External LNA Enable Signal/General-Purpose IO Port.
Regulated Supply for Digital Section. Connect a 1 nF decoupling capacitor from this pin to ground.
Terminal 1 of 32 kHz Crystal Oscillator/General-Purpose IO Port/Analog Test Bus 1.
Rev. 0 | Page 23 of 108
ADF7242
Pin No.
Mnemonic
Description
29
30
XOSC32KN_ATB2
VDD_BAT
Terminal 2 of 32 kHz Crystal Oscillator/Analog Test Bus 2.
Unregulated Supply Input from Battery.
31
32
33 (EPAD)
PAVSUP_ATB3
PABIAOP_ATB4
GND
External PA Supply Terminal/Analog Test Bus 3.
External PA Bias Voltage Output/Analog Test Bus 4.
Common Ground Terminal. The exposed paddle must be connected to ground.
Rev. 0 | Page 24 of 108
ADF7242
TYPICAL PERFORMANCE CHARACTERISTICS
80
70
60
50
40
30
20
10
0
2.0
2.405GHz, 1.8V, +25°C
2.48GHz, 1.8V, +25°C
1.8
2.405GHz, 3.6V, +25°C
2.48GHz, 3.6V, +25°C
1.6
2.405GHz, 1.8V, –40°C
2.48GHz, 1.8V, –40°C
1.4
2.405GHz, 3.6V, –40°C
2.48GHz, 3.6V, –40°C
1.2
2.405GHz, 1.8V, +85°C
2.48GHz, 1.8V, +85°C
1.0
2.405GHz, 3.6V, +85°C
2.48GHz, 3.6V, +85°C
0.8
1.8V, +25°C
0.6
0.4
0.2
0
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
–10
–100
–90
–93
–80
–70
–60
–50
–40
–30
–20
–45 –40 –35 –30 –25 –20 –15 –10 –5
0
5
10 15 20 25 30
RF INPUT POWER LEVEL (dBm)
BLOCKER FREQUENCY OFFSET (MHz)
–96
Figure 15. IEEE 802.15.4-2006 Packet Mode Sensitivity vs. Temperature and
VDD_BAT, fCHANNEL = 2.405 GHz, 2.45 GHz, 2.48 GHz, RFIO2
Figure 18. IEEE 802.15.4-2006 Packet Mode Blocker Rejection vs. Temperature
and VDD_BAT, Modulated Blocker, PWANTED = −85 dBm + 3 dB,
f
CHANNEL = 2.45 GHz, RFIO2
2.0
80
70
60
50
40
30
20
10
0
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
VDD_BAT = 3.6V
TEMPERATURE = 25°C
–10
–20
–100
–90
–80
–70
–60
–50
–40
–30
–20
–110 –90 –70 –50 –30 –10 10
50
70
90 110
RF INPUT POWER LEVEL (dBm)
BLOCKER FREQUENCY OFFSET (MHz)
–96.5 –95
Figure 16. IEEE 802.15.4-2006 Packet Mode PER vs. RF Input Power Level vs.
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, RFIO2
Figure 19. IEEE 802.15.4-2006 Packet Mode Wide-Band Blocker Rejection,
CW Blocker, PWANTED = −95 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
80
70
60
50
40
30
20
10
0
2.0
2.405GHz, 1.8V, +25°C
2.450GHz, 1.8V, +25°C
2.475GHz, 1.8V, +25°C
2.405GHz, 3.6V, +25°C
2.450GHz, 3.6V, +25°C
2.475GHz, 3.6V, +25°C
2.405GHz, 1.8V, –40°C
2.450GHz, 1.8V, –40°C
2.475GHz, 1.8V, –40°C
2.405GHz, 3.6V, –40°C
2.450GHz, 3.6V, –40°C
2.475GHz, 3.6V, –40°C
2.405GHz, 1.8V, +85°C
2.450GHz, 1.8V, +85°C
2.475GHz, 1.8V, +85°C
2.405GHz, 3.6V, +85°C
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
2.450GHz, 3.6V, +85°C
2.475GHz, 3.6V, +85°C
VDD_BAT = 3.6V
TEMPERATURE = 25°C
–10
–20
0.2
0
–20 –16 –12
–8
–4
0
4
8
12
16
20
–100 –98 –96 –94
–92 –90 –88 –86 –84 –82 –80
RF INPUT POWER LEVEL (dBm)
–96 –93
BLOCKER FREQUENCY OFFSET (MHz)
Figure 17. IEEE 802.15.4 Packet Mode Sensitivity vs. Temperature and
VDD_BAT, fCHANNEL = 2.405 GHz, 2.45 GHz, 2.475 GHz, RFIO1
Figure 20. IEEE 802.15.4 Packet Mode Narrow-Band Blocker Rejection,
CW Blocker, PWANTED = −95 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
Rev. 0 | Page 25 of 108
ADF7242
6
5
4
3
2
1
80
70
60
50
40
30
20
10
0
MAX 1.8V, +25°C
MIN 1.8V, +25°C
MAX 3.6V, +25°C
MIN 3.6V, +25°C
MAX 1.8V, –40°C
MIN 1.8V, –40°C
MAX 3.6V, –40°C
MIN 3.6V, –40°C
0
–1
–2
–3
–4
–5
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
MAX 1.8V, +85°C
MIN 1.8V, +85°C
MAX 3.6V, +85°C
MIN 3.6V, +85°C
–6
–10
–95 –90 –85 –80 –75 –70 –65 –60 –55 –50 –45 –40 –35 –30 –25 –20
RF INPUT LEVEL (dBm)
–45 –40 –35 –30 –25 –20 –15 –10 –5
0
5
10 15 20 25 30
BLOCKER FREQUENCY OFFSET (MHz)
Figure 24. IEEE 802.15.4 Packet Mode RSSI Error vs. RF Input Power Level vs.
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, RFIO2
Figure 21. IEEE 802.15.4 Packet Mode Wide-Band Blocker Rejection vs.
Temperature and VDD_BAT, Modulated Blocker, PWANTED = −95 dBm + 3 dB,
f
CHANNEL = 2.45 GHz, RFIO2
80
70
60
50
40
30
20
10
0
275
250
225
200
175
150
125
MAX 1.8V, +25°C
MAX 3.6V, +25°C
MAX 1.8V, –40°C
MAX 3.6V, –40°C
MAX 1.8V, +85°C
MAX 3.6V, +85°C
MIN 1.8V, +25°C
MIN 3.6V, +25°C
MIN 1.8V, –40°C
MIN 3.6V, –40°C
MIN 1.8V, +85°C
MIN 3.6V, +85°C
100
75
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
50
25
0
–10
–100 –95 –90 –85 –80 –75 –70 –65 –60 –55 –50 –45 –40 –35 –30 –25–20
–20 –16 –12
–8
–4
0
4
8
12
16
20
RF INPUT LEVEL (dBm)
INTERFERER FREQUENCY OFFSET (MHz)
Figure 22. IEEE 802.15.4 Packet Mode Narrow-Band Blocker Rejection vs.
Temperature and VDD_BAT, Modulated Blocker, PWANTED = −95 dBm + 3 dB,
fCHANNEL = 2.45 GHz, RFIO2
Figure 25. IEEE 802.15.4 Packet Mode SQI vs. RF Input Power Level vs.
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, RFIO2
110
–20
THRESHOLD =
100
CHANNEL 2.405GHz
CHANNEL 2.48GHz
–22
–80
–70
–60
–50
dBm
–40
dBm
–30
dBm
–20
dBm
dBm
dBm dBm
90
80
70
60
50
40
30
–24
–26
–28
–30
–90
dBm
–32
–34
–36
20
10
0
–110 –90 –70 –50 –30 –10 10
30
50
70
90 110
–90 –85 –80 –75 –70 –65 –60 –55 –50 –45 –40 –35 –30 –25 –20 –15
RF INPUT POWER LEVEL (dBm)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 26. IEEE 802.15.4-2006 CCA Operation vs. RSSI Threshold,
fCHANNEL = 2.45 GHz, VDD_BAT = 3.6 V, Temperature = 25°C, RFIO2 Port
Figure 23. IEEE 802.15.4 Packet Mode Out-of-Band Blocker Rejection,
CW Blocker, PWANTED = −95 dBm + 3 dB, fCHANNEL = 2.405 GHz and 2.48 GHz,
RFIO2, VDD_BAT = 3.6 V, Temperature = 25°C
Rev. 0 | Page 26 of 108
ADF7242
–78
–79
–80
–81
–82
–83
–84
–85
–86
–87
–88
–89
–90
–91
–92
–93
–94
–95
–96
–97
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
VDD_BAT = 3.6V
TEMPERATURE = 25°C
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
2000
1000
500
250
125
100
62.5
50
–90
–80
–70
–60
–50
–40
–30
–20
DATA RATE (kbps)
RF INPUT POWER LEVEL (dBm)
–85 –83
Figure 27. PER vs. RF Input Power Level vs. Temperature and VDD_BAT,
Figure 30. 1% PER sensitivity vs. Data Rate, fCHANNEL = 2.45 GHz, RFIO2
2 Mbps GFSK (fDEV
=
500 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
–1
–2
–3
–4
–5
–6
–7
–8
–100
–90
–87
–80
–70
–60
–50
–40
–30
–20
–90
–80
–92.5 –90.5
–70
–60
–50
–40
–30
–20
RF INPUT POWER LEVEL (dBm)
RF INPUT POWER LEVEL (dBm)
–86
Figure 28. PER vs. RF Input Power Level vs. Temperature and VDD_BAT,
Figure 31. BER vs. RF Input Power Level vs. Temperature and VDD_BAT,
500 kbps GFSK (fDEV
=
250 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2
2 Mbps GFSK (fDEV
=
500 kHz) Mode, fCHANNELS= 2.45 GHz, RFIO2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
–1
–2
–3
–4
–5
–6
–7
–8
–100
–90
–80
–70
–60
–50
–40
–30
–20
–100
–94.5
–90
–92.5
–80
–70
–60
–50
–40
–30
–20
RF INPUT POWER LEVEL (dBm)
RF INPUT POWER LEVEL (dBm)
–90.5
–89
Figure 29. PER vs. RF Input Power Level vs. Temperature and VDD_BAT,
125 kbps FSK (fDEV 60 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2
Figure 32. BER vs. RF Input Power Level vs. Temperature and VDD_BAT,
1 Mbps GFSK (fDEV 250 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2
=
=
Rev. 0 | Page 27 of 108
ADF7242
0
–1
–2
–3
–4
–5
70
60
50
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
40
30
20
10
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
–6
–7
–8
0
–10
–20
–100
–90
–80
–70
–60
–50
–40
–30
–20
–20 –16 –12
–8
–4
0
4
8
12
16
20
RF INPUT POWER LEVEL (dBm)
BLOCKER FREQUENCY OFFSET (MHz)
–94.1 –92.8
Figure 36. Narrow-Band Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 2 Mbps GFSK (fDEV 500 kHz) Packet Mode,
WANTED = −85 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
Figure 33. BER vs. RF Input Power Level vs. Temperature and VDD_BAT,
=
500 kbps GFSK (fDEV
=
250 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2
P
–83
–84
–85
–86
–87
–88
–89
–90
70
60
50
VDD_BAT = 3.6V
TEMPERATURE = 25°C
40
30
20
10
–91
–92
–93
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
–94
–95
0
–10
–96
–97
–20
2000
1000
500
250
125
62.5
50
–100 –80 –60 –40 –20
0
20
40
60
80
100
DATA RATE (kbps)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 34. 0.1% BER Sensitivity vs. Data Rate, fCHANNEL = 2.45 GHz, RFIO2
Figure 37. Wideband Blocker Rejection vs. Temperature and VDD_BAT,
Modulated Blocker, 2 Mbps GFSK (fDEV 500 kHz) Packet Mode,
=
PWANTED = −85 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
70
60
50
70
60
50
40
30
40
30
20
10
20
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
10
0
0
–10
–10
–20
–20
–20 –16 –12
–8
–4
0
4
8
12
16
20
–100 –80 –60 –40 –20
0
20
40
60
80
100
BLOCKER FREQUENCY OFFSET (MHz)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 35. Wideband Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 2 Mbps GFSK (fDEV 500 kHz) Packet Mode,
WANTED = −85 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
Figure 38. Narrow-Band Blocker Rejection vs. Temperature and VDD_BAT,
Modulated Blocker, 2 Mbps GFSK (fDEV 500 kHz) Packet Mode,
PWANTED = −85 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
=
=
P
Rev. 0 | Page 28 of 108
ADF7242
80
70
60
50
40
30
20
10
0
80
70
60
50
40
30
20
10
0
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
–10
–20
–10
–20
–60 –50 –40 –30 –20 –10
0
10 20 30 40 50 60
–20 –16 –12
–8
–4
0
4
8
12
16
20
BLOCKER FREQUENCY OFFSET (MHz)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 39. Wideband Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 125 kbps FSK (fDEV 500 kHz) Packet Mode,
WANTED = −94 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
Figure 42. Narrow-Band Blocker Rejection vs. Temperature and VDD_BAT,
Modulated Blocker,125 kbps FSK (fDEV 60 kHz) Packet Mode,
=
=
P
PWANTED = −94 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
80
70
60
50
40
30
20
10
0
70
60
50
40
30
20
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
10
0
–10
–20
–10
–20
–20 –16 –12
–8
–4
0
4
8
12
16
20
–110 –90 –70 –50 –30 –10 10
30
50
70
90 110
BLOCKER FREQUENCY OFFSET (MHz)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 40. Narrow-Band Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 125 kbps FSK (fDEV 60 kHz) Packet Mode,
Figure 43. Wideband Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 2 Mbps GFSK (fDEV 500 kHz) SPORT Mode,
WANTED = −87.5 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
=
=
PWANTED = −94 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
P
80
70
60
50
40
30
20
10
0
70
60
50
40
30
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
3.6V, +25°C
1.8V, +25°C
3.6V, +85°C
1.8V, +85°C
3.6V, –40°C
1.8V, –40°C
–10
–20
–60 –50 –40 –30 –20 –10
0
10 20 30 40 50 60
–20 –16 –12
–8
–4
0
4
8
12
16
20
BLOCKER FREQUENCY OFFSET (MHz)
BLOCKER FREQUENCY OFFSET (MHz)
Figure 41. Wideband Blocker Rejection vs. Temperature and VDD_BAT,
Modulated Blocker,125 kbps FSK (fDEV 60 kHz) Packet Mode,
PWANTED = −94 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
Figure 44. Narrow-Band Blocker Rejection vs. Temperature and VDD_BAT,
CW Blocker, 2 Mbps GFSK (fDEV 500 kHz) SPORT Mode,
PWANTED = −87.5 dBm + 3 dB, fCHANNEL = 2.45 GHz, RFIO2
=
=
Rev. 0 | Page 29 of 108
ADF7242
4
0
–10
–20
–30
MIN 1.8V, –40°C
MIN 3.6V, –40°C
MIN 1.8V, +85°C
MIN 3.6V, +85°C
MAX 1.8V, +25°C
MAX 1.8V, +85°C
MAX 3.6V, +85°C
MIN 1.8V, +25°C
MIN 3.6V, +25°C
500kbps AFC ON
500kbps AFC OFF
MAX 3.6V, +25°C
MAX 1.8V, –40°C
MAX 3.6V, –40°C
3
2
1
0
–40
–50
–60
–1
–2
–3
–4
–70
–80
–90
–100
–85 –80 –75 –70 –65 –60 –55 –50 –45 –40 –35 –30 –25 –20 –15
RF INPUT POWER LEVEL (dBm)
FREQUENCY ERROR (kHz)
Figure 48. PER vs. Frequency Error with and Without AFC, 500 kbps GFSK
Figure 45. Minimum and Maximum RSSI Error for 1000 Packets vs. RF Input
(fDEV
=
250 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2, VDD_BAT = 3.6 V,
Temperature = 25°C
Power Level vs. Temperature and VDD_BAT, 2 Mbps GFSK (fDEV
Packet Mode, fCHANNEL = 2.45GHz, RFIO2
= 500 kHz)
6
1.2
1.0
0.8
0.6
MAX 1.8V, +25°C
MAX 3.6V, +25°C
MAX 1.8V, –40°C
MAX 3.6V, –40°C
MAX 1.8V, +85°C
MAX 3.6V, +85°C
MIN 1.8V, +25°C
MIN 3.6V, +25°C
5
4
3
2
1
0.4
0.2
PACKET
ERROR
RATE (%)
0
0
–1
–2
–3
–4
–5
–0.2
–0.4
–0.6
–0.8
–1.0
–1.2
–1.4
>1%
<1%
MIN 1.8V, –40°C
MIN 3.6V, –40°C
MIN 1.8V, +85°C
MIN 3.6V, +85°C
–6
–95 –90 –85 –80 –75 –70 –65 –60 –55 –50 –45 –40 –35 –30 –25 –20 –15
RF INPUT POWER LEVEL (dBm)
FREQUENCY ERROR (MHz)
Figure 49. PER vs. Frequency Error vs. Symbol Rate Tolerance, 2 Mbps GFSK
Figure 46. Minimum and Maximum RSSI Error for 1000 Packets vs. RF Input
(fDEV
=
500 kHz) Mode, fCHANNEL = 2.45 GHz, VDD_BAT = 3.6 V,
Temperature = 25°C, RFIO2
Power Level vs. Temperature and VDD_BAT, 500 kbps FSK (fDEV
Packet Mode, fCHANNEL = 2.45 GHz, RFIO2
= 250 kHz)
0
–10
–20
–30
–40
–50
0
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
2Mbps AFC ON
2Mbps AFC OFF
–10
–20
–30
–40
–50
–60
–70
–60
–70
–80
–90
–5
–4
–3
–2
–1
0
1
2
3
4
5
FREQUENCY ERROR (kHz)
FREQUENCY ERROR (kHz)
Figure 47. PER vs. Frequency Error with and Without AFC, 2 Mbps GFSK
Figure 50. IEEE 802.15.4-2006 Transmitter Spectrum vs. Temperature and
VDD_BAT, fCHANNEL = 2.45 GHz, Output Power = 3 dBm
(fDEV
=
500 kHz) Mode, fCHANNEL = 2.45 GHz, RFIO2, VDD_BAT = 3.6 V,
Temperature = 25°C
Rev. 0 | Page 30 of 108
ADF7242
0
–5
2.5
2.4
2.3
2.2
2.1
2.0
1.9
1.8V, +25°C
EVM 1.8V, +25°C
EVM 3.6V, +25°C
EVM 1.8V, –40°C
EVM 3.6V, –40°C
EVM 1.8V, +85°C
EVM 3.6V, +85°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
–10
–15
–20
–25
–30
–35
–40
–45
–50
–55
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
–60
–65
–70
1.0
2405
–1.00 –0.75 –0.50 –0.25
0
0.25
0.50
0.75
1.00
2415
2425
2435
2445
2455
2465
2475
FREQUENCY OFFSET FROM THE RF CARRIER (MHz)
CHANNEL FREQUENCY (MHz)
Figure 54. 125 Mbps FSK (fDEV
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, Output Power = 3 dBm
= 60 kHz) Mode Transmitter Spectrum vs.
Figure 51. IEEE 802.15.4-2006 Transmitter EVM vs. Temperature and
VDD_BAT at All Channels,Output Power = 3 dBm
600
–5
1.8V, +25°C
–10
–15
–20
–25
–30
–35
500
400
300
200
100
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
3.6V, +85°C
1.8V, +85°C
0
–100
–200
–300
–400
–500
–40
–45
–50
–55
–60
–65
–600
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
–5
–4
–3
–2
–1
0
1
2
3
4
5
SYMBOL SAMPLE INSTANT
FREQUENCY OFFSET FROM THE RF CARRIER (MHz)
Figure 55. 2 Mbps GFSK (fDEV
= 500 kHz) Mode Transmitter Eye Diagram,
Figure 52. 2 Mbps GFSK (fDEV
=
500 kHz) Mode Transmitter Spectrum vs.
fCHANNEL = 2.45 GHz, Output Power = 3 dBm, VDD_BAT = 3.6 V,
Temperature = 25°C
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, Output Power = 3 dBm
0
300
1.8V, +25°C
3.6V, +25°C
1.8V, –40°C
3.6V, –40°C
1.8V, +85°C
3.6V, +85°C
–5
250
200
150
100
50
–10
–15
–20
–25
–30
–35
–40
–45
–50
–55
0
–50
–100
–150
–200
–250
–60
–65
–70
–300
–2.5 –2.0 –1.5 –1.0 –0.5
0
0.5
1.0
1.5
2.0
2.5
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
FREQUENCY OFFSET FROM THE RF CARRIER (MHz)
SYMBOL SAMPLE INSTANT
Figure 53. 500 kbps GFSK (fDEV
=
250 kHz) Mode Transmitter Spectrum vs.
Figure 56. 500 kbps FSK (fDEV = 250 kHz) Mode Transmitter Eye Diagram,
Temperature and VDD_BAT, fCHANNEL = 2.45 GHz, Output Power = 3 dBm
fCHANNEL = 2.45 GHz, Output Power = 3 dBm, VDD_BAT = 3.6 V,
Temperature = 25°C
Rev. 0 | Page 31 of 108
ADF7242
10.0
5.5
5.0
4.5
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
9.5
9.0
8.5
8.0
7.5
7.0
4.0
6.5
6.0
5.5
5.0
3.5
3.0
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
2400
2410
2420
2430
2440
2450
2460
2470 2480
2400
2410
2420
2430
2440
2450
2460
2470
2480
RF CARRIER FREQUENCY (MHz)
RF CARRIER FREQUENCY (MHz)
Figure 57. 2 Mbps GFSK (fDEV
=
500 kHz) Mode Transmitter Phase Error vs.
Figure 60. 500 kbps GFSK (fDEV
= 250 kHz) Mode Transmitter Phase Error vs.
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
26.0
8.0
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
25.5
25.0
24.5
24.0
23.5
23.0
22.5
22.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
2400
2410
2420
2430
2440
2450
2460
2470
2480
2400
2410
2420
2430
2440
2450
2460
2470 2480
RF CARRIER FREQUENCY (MHz)
RF CARRIER FREQUENCY (MHz)
Figure 58. 2 Mbps GFSK (fDEV
= 500 kHz) Mode Transmitter MER vs.
Figure 61. 250 kbps GFSK (fDEV
=
250 kHz) Mode Transmitter Phase Error vs.
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
8.0
7.5
7.0
6.5
6.0
5.5
5.0
5.5
5.0
4.5
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
4.0
3.5
3.0
3.6V, +25°C
1.8V, +25°C
3.6V, –40°C
1.8V, –40°C
3.6V, +85°C
1.8V, +85°C
4.5
4.0
2400
2410
2420
2430
2440
2450
2460
2470 2480
2400
2410
2420
2430
2440
2450
2460
2470
2480
RF CARRIER FREQUENCY (MHz)
RF CARRIER FREQUENCY (MHz)
Figure 62. 125 kbps FSK (fDEV
= 60 kHz) Mode Transmitter Phase Error vs.
Figure 59. 1 Mbps GFSK (fDEV
=
250 kHz) Mode Transmitter Phase Error vs.
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
Temperature, VDD_BAT, and Channels, 1 MHz Channel Step,
Output Power = 3 dBm
Rev. 0 | Page 32 of 108
ADF7242
7.0
6.5
6.0
5.5
5.0
2.5
0
–2.5
–5.0
–7.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
–10.0
–12.5
–15.0
–17.5
–20.0
–22.5
–25.0
–27.5
HIGH POWER MODE
DEFAULT MODE
2000
411
409.6
291
289
185
113.6
6
3
4
5
6
7
8
9
10 11 12 13 14 15 16
DATA RATE (kbps)
POWER AMPLIFIER CONTROL WORD
Figure 63. Transmitter Phase Error vs. Data Rate for Each of the Transmitter
Bandwidth LUTs, fCHANNEL = 2.45 GHz, Output Power = 3 dBm
Figure 66. Transmitter Output Power vs. Control Word for Default and High
Power Modes, fCHANNEL = 2.45 GHz, VDD_BAT = 3.6 V, Temperature = 25°C,
RF Carrier Frequency, Temperature, and VDD_BAT
(A discrete matching network and a harmonic filter are used as per the
ADF7242 reference design.)
4.0
3.5
3.0
2.5
2.0
26.0
25.5
25.0
24.5
24.0
HIGH POWER MODE
DEFAULT MODE
23.5
23.0
22.5
22.0
21.5
21.0
20.5
20.0
19.5
19.0
18.5
18.0
17.5
17.0
16.5
16.0
1.5
3.6V, +85°C
3.6V, +25°C
3.6V, –40°C
1.8V, –40°C
1.8V, +25°C
1.0
0.5
1.8V, +80°C
0
2.40
3
4
5
6
7
8
9
10 11 12 13 14 15
2.41
2.42
2.43
2.44
2.45
2.46 2.47
2.48
POWER AMPLIFIER CONTROL WORD
FREQUENCY (GHz)
Figure 64. PA Output Power vs. RF Carrier Frequency, Temperature, and VDD_BAT
(A discrete matching network and a harmonic filter are used as per the
ADF7242 reference design.)
Figure 67. Transmitter Current Consumption vs. Control Word, for Default
and High Power Modes, fCHANNEL = 2.45 GHz, VDD_BAT = 3.6 V,
Temperature = 25°C
85
4
3 SIGMA TEMPERATURE ERROR
TEMPERATURE READING (LINEAR FITTING)
TEMPERATURE READING
80
75
70
2
0
65
60
(POLYNOMIAL FITTING)
–2
55
–4
–6
–8
50
45
40
35
30
–10
–12
–14
25
20
15
10
5
–16
0
–18
–20
3.6V, +85°C
3.6V, +25°C
3.6V, –40°C
1.8V, –40°C
1.8V, +25°C
1.8V, +80°C
–5
–10
–15
–20
–25
–30
–35
–40
–22
–24
–26
–28
–40 –30 –20 –10
0
10 20 30 40 50 60 70 80
TEMPERATURE (°C)
3
4
5
6
7
8
9
10 11 12 13 14 15
PA LEVEL SETTING
Figure 68. Temperature Sensor Performance
(Average of 1000 ADC Readbacks) and 3-∑ Error vs. Temperature,
VDD_BAT = 3.6 V
Figure 65. PA Output Power vs. Control Word, Temperature, and VDD_BAT,
fCHANNEL = 2.44 GHz
(A discrete matching network and a harmonic filter are used as per the
ADF7242 reference design.)
Rev. 0 | Page 33 of 108
ADF7242
TERMINOLOGY
MSK
ACK
Minimum shift keying
IEEE 802.15.4-2006 acknowledgment frame
NC
ADC
Not connected
Analog-to-digital converter
OCL
AFC
Offset correction loop
Automatic frequency correction
OQPSK
AGC
Offset-quadrature phase shift keying
Automatic gain control
PA
Battmon
Battery monitor
Power amplifier
PHR
PHY header
CCA
Clear channel assessment
PHY
Physical layer
BBRAM
Backup battery random access memory
POR
Power-on reset
CRC
Cyclic redundancy check
PSDU
PHY service data unit
CSMA/CA
Carrier-sense-multiple-access with collision avoidance
RC
DR
Data rate
Radio controller
RCO32K
32 kHz RC oscillator
DSSS
Direct sequence spread spectrum
RSSI
FCS
Receive signal strength indicator
Frame check sequence
RTC
Real-time clock
FHSS
Frequency hopping spread spectrum
SFD
FCF
Start-of-frame delimiter
Frame control field
SQI
FSK
Signal quality indicator
Frequency shift keying
SWD
Sync word detect
GFSK
Gaussian frequency shift keying
VCO
LQI
Voltage-controlled oscillator
Link quality indicator
WUC
Wake-up controller
MCR
Modem configuration register
XTO26M
26 MHz crystal oscillator
MCU
Microcontroller unit
XTO32K
32 kHz crystal oscillator
MER
Modulation error ratio
Rev. 0 | Page 34 of 108
ADF7242
RADIO CONTROLLER
COLD START
(BATTERY APPLIED)
CONFIGURE DEVICE
FIRMWARE DOWNLOAD
FOR EXAMPLE, IEEE 802.15.4 AUTO-MODES
WUC TIMEOUT
RC_MEAS
RC_IDLE
CS
MEAS
IDLE
SLEEP
RC_SLEEP
RC_SLEEP
(FROM ANY STATE)
RC_RESET
(FROM ANY STATE)
CCA COMPLETE
RC_PHY_RDY
CCA
PHY_RDY
RC_CCA
RC_TX
RC_RX
RX
TX
RC_RX
RC_TX
2
AUTO_RX_TO_TX_TURNAROUND
AUTO_TX_TO_RX_TURNAROUND
2
1
2
AVAILABLE IN IEEE 802.15.4 MODE OR IN FSK/GFSK PACKET MODE.
THESE TRANSITIONS ARE CONFIGURED IN BUFFERCFG (0x107[3:2]).
KEY
STATE TRANSITION INITIATED BY HOST MCU
AUTOMATIC STATE TRANSITION INITIATED BY RADIO CONTROLLER
RADIO STATE
Figure 69. ADF7242 State Diagram
Rev. 0 | Page 35 of 108
ADF7242
The ADF7242 incorporates a radio controller that manages the
state of the IC in various operating modes and configurations.
The host MCU can use single-byte commands to interface to
the radio controller. The function of the radio controller
includes the control of the sequence of powering up and
powering down various blocks as well as system calibrations in
different states of the device. Figure 69 shows the state diagram
of the ADF7242 with possible transitions that are initiated by
the host MCU and automatically by the radio controller.
The PHY_RDY state can be entered from the idle, RX, TX, or
CCA state by issuing an RC_PHY_RDY command.
RX State
The RF frequency synthesizer is automatically calibrated to the
programmed channel frequency upon entering the RX state
from the PHY_RDY or TX state. The frequency synthesizer
calibration can be omitted for single-channel communication
systems if short turnaround times are required. Following a
programmable MAC delay period, the ADF7242 starts
searching for a preamble and a synchronization word if enabled
by the user.
Device Initialization
When the battery voltage is first applied to the ADF7242, a cold
start-up sequence should be followed, as shown in Figure 70.
The start-up sequence is as follows:
The RX state can be entered from the PHY_RDY, CCA, and TX
states by issuing an RC_RX command. Depending on whether
the device is configured to operate in packet or SPORT mode by
setting Register buffercfg, Field rx_buffer_mode, the device can
revert automatically to the PHY_RDY state when a packet is
received, or remain in the RX state until a command to enter a
different state is issued. Refer to the Receiver section for further
details.
•
Apply the battery voltage, VDD_BAT, to the device with
the desired voltage ramp rate. After a time, tRAMP
VDD_BAT reaches its final voltage value.
,
•
•
•
After tRAMP, execute the SPI command, RC_RESET. This
command resets and shuts down the device.
CS
After the specified time, t15, the host MCU can set the
port of the SPI low.
CCA State
Wait until the MISO output of the SPI (SPI_READY flag)
goes high, at which time the device is in the idle state and
ready to accept commands.
Upon entering the CCA state, a clear channel assessment is
performed. The CCA state can be entered from the PHY_RDY
or RX state by issuing an RC_CCA command. By default, upon
completion of the clear channel assessment, the ADF7242
automatically reverts to the state from which the RC_CCA
command originated.
CS
A power-on reset takes place when the host MCU sets the
port of the SPI low. All device LDOs are enabled together with
the 26 MHz crystal oscillator and the digital core. After the
radio controller initializes the configuration registers to their
default values, the device enters the idle state.
TX State
Upon entering the TX state, the RF frequency synthesizer is
automatically calibrated to the programmed channel frequency.
The frequency synthesizer calibration can be omitted for
communication systems operating on a single channel if short
turnaround times are required. Following a programmable
delay period, the PA is ramped up and transmission is initiated.
The cold start-up sequence is needed only when the battery
voltage is first applied to the device. Afterwards, a warm start-
up sequence can be used where the host MCU can wake up the
CS
device from a sleep state by setting the
port of the SPI low.
Idle State
The TX state can be entered from the PHY_RDY or RX state by
issuing the RC_TX command. Depending on whether the
device is configured to operate in packet or SPORT mode by
setting Register buffercfg, Field rx_buffer_mode, the device can
revert automatically to the PHY_RDY state when a packet is
transmitted, or remain in the TX state until a command to enter
a different state is issued. Refer to the Transmitter section for
further details.
In this state, the receive and transmit blocks are powered down.
The digital section is enabled and all configuration registers as
well as the packet RAM are accessible. The host MCU has to set
any configuration parameters, such as modulation scheme,
channel frequency, and WUC configuration in this state.
CS
Bringing the
input low in the sleep state causes a transition
into the idle state. The transition from the sleep state to the idle
state timing is shown in Figure 4. The idle state can also be
entered by issuing an RC_IDLE command in any state other
than the sleep state.
MEAS State
The MEAS state is used to measure the chip temperature. The
transmitter and receiver blocks are not enabled in this state.
The chip temperature is measured using the ADC, which can
be read from Register adc_rbk, Field adc_out, and is
PHY_RDY State
Upon entering the PHY_RDY state from the idle state, the RF
frequency synthesizer is enabled and a system calibration is
carried out. The receive and transmit blocks are not enabled
in this state. The system calibration is omitted when the
PHY_RDY state is entered from the RX, TX, or CCA state.
continuously updated with the chip temperature reading.
This state is enabled by issuing the RC_MEAS command from the
idle state and can be exited using the RC_IDLE command.
Rev. 0 | Page 36 of 108
ADF7242
Sleep States
SLEEP_BBRAM_XTO
The sleep state is entered with the RC_SLEEP command. The
sleep state can be configured to operate in three different
modes, which are listed in Table 21.
This mode enables the 32 kHz crystal oscillator and retains
certain configuration registers in the BBRAM during the sleep
state. To enable SLEEP_BBRAM_XTO mode, set Register
tmr_cfg1, Field sleep_config = 5. A wake-up interrupt can be
set using, for example, Register irq1_en0, Field wakeup = 1.
Refer to the Wake-Up Controller (WUC) section for details on
how to configure the ADF7242 WUC.
Table 21. ADF7242 Sleep Modes
Active
Circuits
Sleep Mode
Functionality
SLEEP_BBRAM
BBRAM
Packet RAM and modem
configuration register (MCR)
contents are not maintained.
BBRAM retains the IEEE
802.15.4-2006 node
SLEEP_BBRAM_RCO
This mode enables the 32 kHz RC oscillator and retains certain
configuration registers in the BBRAM during the sleep state.
This mode can be used when lower timer accuracy is acceptable
by the communication system. It is enabled by setting Register
tmr_cfg1, Field sleep_config = 11. A wake-up interrupt can be
set using, for example, Register irq1_en0, Field wakeup = 1.
Refer to the Wake-Up Controller (WUC) section for details on
how to configure the ADF7242 WUC.
addresses1.
SLEEP_BBRAM_XTO BBRAM and
32 kHz crystal oscillator is
enabled, with data retention
in the BBRAM.
32 kHz
crystal
oscillator
SLEEP_BBRAM_RCO BBRAM and
32 kHz RC oscillator is
enabled, with data retention
in the BBRAM.
32 kHz RC
Oscillator
Wake-Up from the Sleep State
1 Refer to the IEEE 802.15.4-2006 Receiver Configuration in Packet Mode
section for further details.
CS
The host MCU can bring
low at any time to wake the
CS
ADF7242 from the sleep state. After bringing
low, it must
SLEEP MODES
wait until the MISO output (SPI_READY flag) goes high prior
to accessing the SPI port. This delay reflects the start-up time of
the ADF7242. When the MISO output is high, the voltage
regulator of the digital section and the crystal oscillator have
stabilized. Unless the chip is in the sleep state, the MISO pin
The sleep modes are configurable with the wake-up configura-
tion registers, tmr_cfg0 and tmr_cfg1. The contents of Register
tmr_cfg0 and Register tmr_cfg1 are reset in the sleep state.
SLEEP_BBRAM
CS
always goes high immediately after bringing
low. The sleep
This mode is suitable for applications where the MCU is equipped
with its own wake-up timer. SLEEP_BBRAM mode is enabled
by setting Register tmr_cfg1, Field sleep_config = 1.
state can also be exited by a timeout event with the WUC
configured. Refer to the Wake-Up Controller (WUC) section
for details on how to configure the ADF7242 WUC.
t15
APPLY
VDD_BAT
CS
RC_RESET
(0xC8)
SPI COMMAND
TO ADF7242
DEVICE STATE
IDLE
SLEEP
IDLE
Figure 70. Cold Start Sequence from Application of the Battery
Rev. 0 | Page 37 of 108
ADF7242
RF FREQUENCY SYNTHESIZER
scheme is used to mitigate the effect of temperature, supply
voltage, and process variations on the VCO performance.
A fully integrated RF frequency synthesizer is used to generate
both the transmit signal and the receive LO signal. The
architecture of the frequency synthesizer is shown in Figure 71.
The receiver uses the frequency synthesizer circuit to generate
the local oscillator (LO) for downconverting an RF signal to the
baseband. The transmitter is based on a direct closed-loop VCO
modulation scheme using a low noise fractional-N RF
frequency synthesizer, where a high resolution Σ-Δ modulator
is used to generate the required frequency deviations at the RF
in response to the data being transmitted.
The VCO calibration phase must not be skipped during the
system calibration in the PHY_RDY state. Therefore, it is
important to ensure that Register vco_cal_cfg, Field skip_vco_cal
= 9 prior to entering the PHY_RDY state from the idle state.
This is the default setting and, therefore, only requires program-
ming if skipping of the calibration was previously selected.
The VCO calibration can be skipped on the transition from the
PHY_RDY state to the RX, TX, and CCA states on the
condition that the calibration has been performed in the
PHY_RDY state on the same channel frequency to be used in
the RX, TX, and CCA states. The following sequence should be
used if skipping the VCO calibration is required in any state
following the PHY_RDY state:
The VCO and the frequency synthesizer loop filter of the
ADF7242 are fully integrated. To reduce the effect of VCO
pulling by the power-up of the power amplifier, as well as to
minimize spurious emissions, the VCO operates at twice the RF
frequency. The VCO signal is then divided by 2 giving the
required frequency for the transmitter and the required LO
frequency for the receiver. The frequency synthesizer also
features automatic VCO calibration and bandwidth selection.
1. After the system calibration is performed in the PHY_RDY
state, the VCO frequency band in Register vco_band_rb,
Field vco_band_val_rb and the VCO bias DAC code in
Register vco_idac_rb, Field vco_idac_val_rb should be read
back.
RX AND TX
CIRCUITS
CHANNEL SELECTION
2. Before transitioning to any other state and assuming
operation on the same channel frequency, the VCO
frequency band and amplitude DAC should be overwritten
as follows:
IN RX OR TX
SDM
PFD
N-DIVIDER
DIV2
GFSK OR FSK TX DATA
CHARGE-PUMP
AND
LOOP FILTER
26MHz XOSC
+ DOUBLER
a) Set Register vco_cal_cfg, Field skip_vco_cal = 15 to
skip the VCO calibration.
AUTO SYNTH
BANDWIDTH
SELECTION
b) Enable the VCO frequency over-write mode by setting
Register vco_ovrw_cfg, Field vco_band_ovrw_en = 1.
c) Write the VCO frequency band read back after the
system calibration in the PHY_RDY state to Register
vco_band_ovrw, Field vco_band_ovrw_val.
VCO
CALIBRATION
Figure 71. Synthesizer Architecture
RF FREQUENCY SYNTHESIZER CALIBRATION
The ADF7242 requires a system calibration prior to being
used in the RX, CCA, or TX state. Because the calibration
information is reset when the ADF7242 enters a sleep state, a
full system calibration is automatically performed on the
transition between the idle and PHY_RDY states. The system
calibration is omitted when the PHY_RDY state is entered from
the TX, RX, or CCA state.
d) Enable the VCO bias DAC over-write mode by setting
Register vco_ovrw_cfg, Field vco_idac_ovrw_en = 1
e) Write the VCO bias DAC read back after the system
calibration in the PHY_RDY state to Register
vco_idac_ovrw, Field vco_idac_ovrw_val .
Following the preceding procedure, the device can transition
to other states, which use the same channel frequency without
performing a VCO calibration. If it is required to change the
channel frequency before entering the RX, TX, or CCA state at any
point after the preceding procedure has been used, Register vco_
cal_cfg, Field skip_vco_cal must be set to 9 before transitioning
to the respective state. Then the VCO calibration is automati-
cally performed.
142µs
SYNTHESIZER
PWR Up RC Cal
24µs 20µs
VCO Cal
52µs
SETTLING
46µs
DO NOT SKIP,
SET REGISTER vco_cal_cfg, FIELD skip_vco_cal = 9
Figure 72. System Calibration Following RC_PHY_RDY
RF FREQUENCY SYNTHESIZER BANDWIDTH
Figure 72 shows a breakdown of the total system calibration
time. It comprises a power-up delay, calibration of the receiver
baseband filter (RC Cal), and a VCO calibration (VCO Cal). Once
the VCO is calibrated, the frequency synthesizer is allowed to
settle to within 5 ppm of the target frequency. A fully
automatic fast VCO frequency and amplitude calibration
The ADF7242 radio controller optimizes the RF frequency
synthesizer bandwidth based on whether the device is in the RX
or the TX state. If the device is in the RX state, the frequency
synthesizer bandwidth is set by the radio controller to ensure
optimum blocker rejection. If the device is in the TX state, the
radio controller sets the frequency synthesizer bandwidth based
Rev. 0 | Page 38 of 108
ADF7242
on the required data rate to ensure optimum modulation
quality. The frequency synthesizer bandwidth is optimized for
the recommended modulation schemes, data rates, and fre-
quency deviations given in Table 22. If the user requires a
different modulation scheme or data rate from those listed in
Table 22, it is recommended, for optimum device performance,
to choose a frequency deviation for the required data rate that
gives a modulation index close to those recommended in Table 22.
REFERENCE CRYSTAL OSCILLATOR
The on-chip crystal oscillator generates the reference frequency
for the frequency synthesizer and system timing. The oscillator
operates at a frequency of 26 MHz. The crystal oscillator is
amplitude controlled to ensure a fast start-up time and stable
operation under different operating conditions. The crystal and
associated external components should be chosen with care
because the accuracy of the crystal oscillator can have a significant
impact on the performance of the communication system. Apart
from the accuracy and drift specification, it is important to
consider the nominal loading capacitance of the crystal.
Crystals with a high loading capacitance are less sensitive to
frequency pulling due to tolerances of external capacitors and the
printed circuit board parasitic capacitances. When selecting a
crystal, these advantages should be balanced against the higher
current consumption, longer start-up time, and lower trimming
range resulting from a larger loading capacitance.
RF CHANNEL FREQUENCY PROGRAMMING
The frequency of the synthesizer is programmed with the
frequency control word, ch_freq[23:0], which extends over
Register ch_freq0, Register ch_freq1, and Register ch_freq2.
The frequency control word, ch_freq[23:0], contains a binary
representation of the absolute frequency of the desired channel
divided by 10 kHz.
Writing a new channel frequency value to the frequency control
word ch_freq[23:0] takes effect after the next frequency
synthesizer calibration phase. The frequency synthesizer is
calibrated by default during the transition into the PHY_RDY
from the idle state as well as in the TX, RX and CCA states.
Refer to the RF Frequency Synthesizer Calibration, Transmitter,
and Receiver sections for further details. To facilitate fast
channel frequency changes, a new frequency control word can
be written in the RX state before a packet has been received.
The next RC_RX o RC_TX command initiates the required
frequency synthesizer calibration and settling cycle. Similarly, a
new frequency control word can be written after a packet has
been transmitted while in the TX state and the next RC_RX or
RC_TX command initiates the frequency synthesizer
calibration and settling cycle.
The total loading capacitance must be equal to the specified
load capacitance of the crystal and comprises the external
parallel loading capacitors, the parasitic capacitances of the
XOSC26P and XOSC26N pins, as well as the parasitic
capacitance of tracks on the printed circuit board.
The ADF7242 has an integrated crystal oscillator tuning capacitor
that facilitates the compensation of systematic production
tolerance and temperature drift. The tuning capacitor is con-
trolled with Register xto26_trim _cal, Field xto26_trim (0x371).
The tuning range provided by the tuning capacitor depends on
the loading capacitance of a specific crystal. The total tuning
range is typically 25 ppm
Rev. 0 | Page 39 of 108
ADF7242
TRANSMITTER
TRANSMITTER IN IEEE 802.15.4-2006 MODE
IEEE 802.15.4-2006 Transmission
TRANSMIT OPERATING MODES
The four primary transmitter operating modes are:
IEEE 802.15.4-2006-compatible mode with packet manager
support is selected with Register rc_cfg, Field rc_mode = 0
(0x13E). In this mode, the ADF7242 packet manager automati-
cally generates the IEEE 802.15.4-2006-compatible preamble
and SFD. There is also an option to use a nonstandard SFD by
programming Register sfd_15_4 with the desired alternative
SFD. Refer to the IEEE 802.15.4-2006 Programmable SFD
subsection of the Receiver in IEEE 802.15.4-2006 Mode section
for further details. There are 256 bytes of dedicated RAM
(packet RAM), which constitute TX_BUFFER and RX_BUFFER,
available to store transmit and receive packets. The packet
header must be the first byte written to TX_BUFFER. The address
of the first byte of TX_BUFFER is stored in Register txpb, Field
tx_pkt_base.
•
•
•
•
IEEE 802.15.4-2006 packet mode
IEEE 802.15.4-2006 SPORT mode
GFSK/FSK packet mode
GFSK/FSK SPORT mode
The desired mode of operation is selected via Register rc_cfg,
Field rc_mode. The ADF7242 supports GFSK/FSK modulation
with the data rates listed in Table 22. The ADF7242 also fully
supports user-defined data rates between 50 kbps and 2 Mbps
for FSK mode of operation. The data rate, DR, is set with
Register dr0, Field data_rate_high and Register dr1, Field
data_rate_low according to the following equation:
DR = (data_rate_high × 256 + data_rate_low) × 100 bps
The default values of the dr0 and dr1 registers configure the device
for IEEE 802.15.4-2006 mode.
If the automatic FCS field generation has been disabled
(Register pkt_cfg, Field auto_fcs_off = 1), the full frame
including FCS must be written to TX_BUFFER. In this case, the
number of bytes written to TX_BUFFER must be equal to the
length specified in the PHR field.
For GFSK/FSK data rates greater than 250 kbps and IEEE 802.15.4-
2006 mode, the modulator preemphasis filter must be enabled with
Register tx_m, Field preemp_filt = 1. The modulator of the
ADF7242 has an optional Gaussian symbol filter that can be
enabled with Configuration Register tx_m, Field gauss_filt = 1.
The BT product of the Gaussian symbol filter is fixed at 0.5.
This can be used for improved spectral efficiency. Gaussian
filtering must be disabled for IEEE 802.15.4-2006 mode.
If automatic FCS field generation has been enabled (Register
pkt_cfg, Field auto_fcs_off = 0), the FCS is automatically
appended to the frame in TX_BUFFER. In this case, the
number of bytes written to TX_BUFFER must be equal to the
length specified in the PHR field minus two.
The deviation frequency (fDEV) of the modulator is programma-
ble with Register tx_fd, Field tx_freq_dev in steps of 10 kHz.
Refer to the Device Configuration section for recommended
settings for Register tx_fd, Field tx_freq_dev corresponding
with the recommended modulation parameters listed in Table 22.
The default value of Register tx_fd, Field tx_freq_dev configures
the correct setting for IEEE 802.15.4-2006 mode. If the user
requires a different modulation scheme or data rate from those
listed in Table 22, it is recommended, for optimum device
performance, to choose a frequency deviation for the required
data rate that gives a modulation index close to those recom-
mended in Table 22
The format of the frame in TX_BUFFER, both with automatic
FCS field generation enabled and with it disabled, is shown in
Figure 73.
Details of how to configure IEEE 802.15.4-2006 TX SPORT
mode are given in the SPORT Interface section.
Table 22. Recommended Modulation Schemes
Bit rate (kbps)
Modulation Type
DSSS-OQPSK
GFSK/FSK
Description
250
62.5
125
IEEE 802.15.4-2006 compliant
fDEV = 60 kHz
fDEV = 60 kHz
GFSK/FSK
250
500
1000
2000
GFSK/FSK
GFSK/FSK
GFSK/FSK
GFSK/FSK
fDEV = 130 kHz
fDEV = 250 kHz
fDEV = 250 kHz
fDEV = 500 kHz
Rev. 0 | Page 40 of 108
ADF7242
1
2
1
0 TO 20
n
2
ADDRESS
INFORMATION
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 1
REGISTER txpb, FIELD tx_pkt_base
REGISTER txpb, FIELD tx_pkt_base
+ 5 + (0 to 20) + n
REGISTER rc_cfg, FIELD rc_mode = 0
1
2
1
0 TO 20
n
ADDRESS
INFORMATION
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 0
REGISTER txpb, FIELD tx_pkt_base
REGISTER txpb, FIELD tx_pkt_base
+ 5 + (0 to 20) + n – 2
Figure 73. Field Format of TX_BUFFER
and Register delaycfg2, Field mac_delay_ext. Register delaycfg1,
Field tx_mac_delay is programmable in steps of 1 μs, whereas
Register delaycfg2, Field mac_delay_ext is programmable in
steps of 4 μs. The default value of Register delaycfg1, Field
tx_mac_delay is the length of 12 IEEE 802.15.4-2006-2.4 GHz
symbols or 192 μs.
IEEE 802.15.4-2006 Transmitter Timing and Control
This section applies when IEEE 802.15.4-2006 packet mode is
enabled. Accurate control over the transmission slot timing is
maintained by two delay timers (Register delaycfg1, Field
tx_mac_delay and Register delaycfg2, Field mac_delay_ext),
which introduce a controlled delay between the rising edge of the
The default value of Register delaycfg2, Field mac_delay_ext is
0 μs. Following the issue of the RC_TX command, while the
delay defined by Register delaycfg1, Field tx_mac_delay is
elapsing, Register delaycfg2, Field mac_delay_ext can be
updated up until the time, t27, specified in Table 13. This allows
a dynamic adjustment of the transmission timing for acknowl-
edge (ACK) frames for networks using slotted CSMA/CA. To
ensure correct settling of the synthesizer prior to PA ramp-up,
the total TX MAC delay should not be programmed to a value
shorter than specified by the PHY_RDY or RX to TX timing
specified in Table 10. The RC_TX command can be aborted up
to the time specified by Parameter t28 in Table 13 by means of
issuing an RC_PHY_RDY, RC_RX, or RC_IDLE command.
CS
signal following the RC_TX command and the start of the
transmit operation. Figure 74 illustrates the timing of the
transmit operation assuming that the ADF7242 was operating
in PHY_RDY, RX, or TX state prior to the execution of an
RC_TX command.
If enabled, the external PA interface, as described in the Power
Amplifier section, is powered up prior to the synthesizer calibra-
tion to allow sufficient time for the bias servo loop to settle.
Ramp-up of the PA is completed shortly before the overall MAC
delay has elapsed. If enabled, an rc_ready interrupt (see the
Interrupt Controller section) is generated at the transition into
the TX state. Following the completion of the PA ramp-up
phase, the transceiver enters the TX state. The minimum and
maximum time for the PA ramp-up to complete prior to the
transceiver entering the TX state given by Parameter t35 in
Table 14 also applies to IEEE 802.15.4-2006 transmit mode.
The VCO calibration (VCO_cal) can be skipped if shorter turna-
round times are required. Skipping the VCO calibration is
possible if the channel frequency control word ch_freq[23:0]
has remained unchanged since the last RC_PHY_RDY, RC_RX,
RC_CCA, or RC_TX command was issued with VCO_cal
enabled. The initialization, synthesizer settling, and PA ramping
phases are mandatory however because the synthesizer
bandwidth is changed between receive and transmit operation.
Skipping the VCO calibration is an option for single-channel
communication systems, or systems where an ACK frame is
transmitted on the same channel upon reception of a packet.
The radio controller first transmits the automatically generated
preamble and SFD. If it has been enabled, an SFD interrupt is
asserted after the SFD is transmitted. The packet manager then
reads TX_BUFFER, starting with the PHR byte and transmits
its contents. Following the transmission of the entire frame, the
radio controller turns the PA off and asserts a tx_pkt_sent
interrupt. The ADF7242 then automatically returns to the
PHY_RDY state unless automatic operating modes have been
configured.
VCO_cal is skipped by setting Register vco_cal_cfg, Field
skip_vco_cal = 15. In this case, tx_mac_delay can be reduced to
140 μs. The VCO calibration is executed if Register vco_cal_cfg,
Field skip_vco_cal = 9.
By default, the synthesizer is recalibrated each time an RC_TX
command is issued. Figure 75 shows the synthesizer calibration
sequence that is performed each time the transceiver enters the
TX state. The total TX MAC delay is defined by the combined
delay configured with Register delaycfg1, Field tx_mac_delay
Rev. 0 | Page 41 of 108
ADF7242
EXTERNAL
PA BIAS
PA OUTPUT
POWER
TRANSMITTED
PACKET
PREAMBLE SFD PHR PSDU
RC_TX
PREVIOUS STATE
TX
PHY_RDY
RC_STATUS
tx_mac_delay +
mac_delay_ext
OPERATION
SYNTH CALIBRATION
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src1, FIELD tx_sfd
REGISTER irq_src1, FIELD tx_pkt_sent
Figure 74. Transmit Timing and Control (IEEE 802.15.4-2006 Mode)
192µs
0µs TO 1020µs
mac_delay_ext
tx_mac_delay
154µs
SYNTHESIZER
SETTLING
PA
RAMP
PA
RAMP
. . . . . . . . . . . . .
INIT
VCO_cal
22µs
52µs
80µs
<6µs
<6µs
SKIPPED IF
REGISTER vco_cal_cfg,
FIELD skip_vco_cal = 15
Figure 75. Synthesizer Calibration Following RC_TX
PACKET
TRANSMITTED
FRAME IN TX_BUFFER
PACKET
RECEIVED
VALID IEEE802.15.4-2006 FRAME
PHY_RDY
RC_STATUS
RX
TX
tx_mac_delay +
mac_delay_ext
t26
t27,t28
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src1, FIELD rx_pkt_rcvd
REGISTER irq_src1, FIELD tx_pkt_sent
Figure 76. IEEE 802.15.4 Auto RX-to-TX Turnaround Mode
Rev. 0 | Page 42 of 108
ADF7242
Preamble
IEEE 802.15.4 AUTOMATIC RX-TO-TX
TURNAROUND MODE
The preamble is a 0xAA sequence, with a programmable length.
It is necessary to have preamble at the beginning of the packet
to allow time for the receiver AGC, AFC, and clock and data
recovery circuitry to settle before the start of the sync word. The
required preamble length depends on the radio configuration.
Table 38 in the Configuration Values for GFSK/FSK Packet and
SPORT Modes section provides data on required preamble
length for some examples of different configurations.
The ADF7242 features an automatic RX-to-TX turnaround mode
when it is operating in IEEE 802.15.4-2006 packet mode
(Register rc_cfg, Field rc_mode = 0). The automatic RX-to-TX
turnaround mode facilitates the timely transmission of
acknowledgment frames.
Figure 76 illustrates the timing of the automatic RX-to-TX
turnaround mode. When enabled by setting Register buffercfg,
Field auto_rx_to_tx_turnaround, the ADF7242 automatically
enters the TX state following the reception of a valid IEEE
802.15.4-2006 frame. After the combined transmit MAC delay
(tx_mac_delay + mac_delay_ext), the ADF7242 enters the TX
state and transmits the frame stored in TX_BUFFER. After the
transmission is complete, the ADF7242 enters the PHY_RDY
state. There is a 38 μs delay between the reception of the last
symbol and the generation of the rx_pkt_rcvd interrupt. The
transmit MAC delay timeout period begins immediately after
the reception of the last symbol. Therefore, the host MCU has
up to t28 μs (see Table 13) after a frame has been received to cancel
the transmit operation by means of issuing an RC_IDLE,
RC_PHY_RDY, or RC_RX command.
The total length of the preamble transmitted is equal to the
number of bytes set in Register fsk_preamble (0x102) added to
the number of bytes set in Register preamble_num_validate
(0x3F3), along with any additional preamble bits required to
pad the SWD (see the Sync Word (SWD) section for details).
Sync Word (SWD)
The value of the SWD is set in the sync_word0, sync_word1,
and sync_word2 registers (0x10C, 0x10D, and 0x10E). The
SWD is transmitted most significant bit first starting with
sync_word2. The transmitted sync word is a multiple of eight
bits. Therefore, for nonbyte length sync words, the transmitted
sync pattern should be padded with the preamble pattern, as
shown in Table 24.
TRANSMITTER IN GFSK/FSK MODE
Packet Mode GFSK/FSK Transmission
Payload Length
The payload length is defined as the number of bytes from the
end of sync word to the start of the CRC.
The packet manager provides support for proprietary GFSK/
FSK payload formats. Packet fields applicable to GFSK/FSK
packet mode are shown in Table 23. In transmit mode, the
packet manager can be configured to add preamble and sync
words to the payload data stored in the packet RAM. It can also
optionally calculate and transmit a CRC word.
CRC
An optional CRC-16 can be appended to the packet. The CRC
polynomial used is:
g(x) = x16 + x12 + x5 + 1
To enable GFSK/FSK transmit packet mode operation, set
Register rc_cfg, Field rc_mode = 4; 0x13E[7:0]). The host MCU
writes the payload data to the packet ram. The location of
transmit data in the packet RAM is defined by the value in
Register tx_pb, Field tx_pkt_base (Location 0x314). This holds
the address of the first byte of the transmit payload data in the
packet RAM.
To disable the automatic appending of a CRC to the packet, set
Register pkt_cfg, Field auto_fcs_off = 1. This field is set to 0 by
default.
Postamble
The packet manager automatically appends two bytes of
postamble to the end of the transmitted packet. Each byte of
postamble is 0xAA.The first byte is transmitted immediately
after the CRC. The PA ramp-down begins immediately after the
first postamble byte. The second byte is transmitted while the
PA is ramping down.
The preamble, sync word, and CRC word can be automatically
added by the packet manager to the data stored in the packet
RAM for transmission. Figure 77 shows the fields stored in the
packet buffer.
Table 23. Description of Fields Applicable to GFSK/FSK Packet Transmission
Packet Structure
Payload
Field
Preamble
SWD
Length
Payload Data
CRC
Postamble
Field Length
Optional Field
Added in Transmit and Removed in Receive
Host Writes These Fields to Packet RAM
Fully Programmable Parameter
1 to 256 bytes 1 to 4 bytes 2 bytes
0 to 127 bytes
2 bytes
Yes
Yes
Optional No
No No
1 byte
No
Yes
No
No
Yes
No
Yes
N/A
N/A
Yes
Yes
N/A
N/A
Yes
Yes
Yes
No
Only length
Rev. 0 | Page 43 of 108
ADF7242
Table 24. Sync Word Programming Examples
Register
Required Sync Word (Binary, Sync_confg,
sync_
sync_
sync_
Transmitted Sync Word (Binary,
Receiver Sync Word
Match Length (Bits)
First Bit Being First in Time)
000100100011010001010110
111010011100101000100
0001001000110100
011100001110
Field sync_len
word2 word1 word0 First Bit Being First in Time)
24
21
16
12
8
0x12
0xBD
0xAA
0xAA
0xAA
0xAA
0x34
0x39
0x12
0xA7
0xAA
0xAA
0x56
0x44
0x34
0x0E
0x12
0x9C
0001_0010_0011_0100_0101_0110
1011_1101_0011_1001_0100_0100
1010_1010_0001_0010_0011_0100
1010_1010_1010_0111_0000_1110
1010_1010_1010_1010_0001_0010
1010_1010_1010_1010_1001_1100
24
21
16
12
8
00010010
011100
6
6
n = 1 TO 252
2
2
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 1
REGISTER txpb, FIELD tx_pkt_base
REGISTER txpb, FIELD tx_pkt_base
2 + n
REGISTER rc_cfg, FIELD rc_mode = 4
n = 1 TO 254
2
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 0
REGISTER txpb, FIELD tx_pkt_base
Figure 77. Format of GFSK/FSK Packets Stored by the Packet Manager in TX_BUFFER
EXTERNAL PA BIAS
PA OUTPUT POWER
PREAMBLE SWD
PAYLOAD
POSTAMBLE
TRANSMITTED PACKET
RC_TX
RC_STATUS
PREVIOUS STATE
TX
PHY_RDY
FIELD tx_mac_delay +
mac_delay_ext
OPERATION
SYNTH CALIBRATION
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src0, FIELD tx_sfd
REGISTER irq_src0, FIELD tx_pkt_sent
Figure 78. TX Timing and Control GFSK/FSK Packet Mode
Rev. 0 | Page 44 of 108
ADF7242
SPORT MODE GFSK/FSK Transmitter Timing and Control
packet format is entirely under user control, no tx_sfd and
tx_pkt_sent interrupts are generated. The calibration sequence
shown in Figure 75 in the IEEE 802.15.4-2006 Transmitter
Timing and Control section is fully applicable to GFSK/FSK
transmit SPORT mode.
For GFSK/FSK TX SPORT mode operation, set Register rc_cfg,
Field rc_mode = 3; 0x13E[7:0]). Refer to the SPORT Interface
section for further details.
Figure 79 illustrates the timing of the transmit operation in
GFSK/FSK TX SPORT mode. Following the transition into the
TX state, the packet manager transmits SPORT input data until
the TX state is left with an appropriate command. Because the
Table 25 shows the latency between data at the SPORT interface
input and the modulated RF output signal transmitted.
EXTERNAL
PA BIAS
PA OUTPUT
POWER
TRANSMITTED
PACKET
SPORT INPUT DATA
RC_PHY_RDY
RC_TX
RC_STATUS
PREVIOUS STATE
TX
PHY_RDY
tx_mac_delay +
mac_delay_ext
OPERATION
SYNTH CALIBRATION
REGISTER irq_src0, FIELD rc_ready
Figure 79. TX Timing and Control (GFSK/FSK SPORT Mode)
Table 25. Transmit Latency for Selected Data Rates
Bit Rate (kbps)
GFSK
FSK
62.5
125
250
500
1000
2000
32 μs (two bit periods)
16 μs (two bit periods)
8 μs (two bit periods)
4 μs (two bit periods)
2 μs (two bit periods)
1 μs (two bit periods)
8.025 μs (~½ bit period)
4.063 μs (~½ bit period)
2.063 μs (~½ bit period)
1.063 μs (~½ bit period)
563 ns (~½ bit period)
332 ns (~½ bit period)
Rev. 0 | Page 45 of 108
ADF7242
External PA Interface
POWER AMPLIFIER
The ADF7242 has an integrated biasing block for external PA
circuits as shown in Figure 81. It is suitable for external PA circuits
based on a single GaAs MOSFET and a wide range of integrated
PA modules. The key components are shown in Figure 82. A
switch between Pin VDD_BAT and Pin PAVSUP_ATB3 controls
the supply current to the external FET. PABIOP_ATB4 can be
used to set a bias point for the external FET. The bias point is
controlled by a 5-bit DAC and/or a bias servo loop.
The integrated power amplifier (PA) is connected to the RFIO2P
and RFIO2N RF ports. It is equipped with a built-in harmonic
filter to simplify the design of the external harmonic filter. The
output power of the PA is set with Register extpa_msc, Field
pa_pwr with an average step size of 2 dB. The step size increases
at the lower end of the control range. Refer to Figure 65 for the
typical variation of output power step size with the control word
value. The PA also features a high power mode, which can be
enabled by setting Register pa_bias, Field pa_bias_ctrl = 63 and
Register pa_cfg, Field pa_bridge_dbias = 21.
To have the external PA interface under direct control of the
host MCU, set Register ext_ctrl, Field extpa_auto_en = 0. The host
MCU can then use Register pd_aux, Field extpa_bias_en to enable
or disable the external PA. If Register ext_ctrl, Field extpa_auto_en
= 1, the external PA automatically turns on when entering, and
turns off when exiting the TX state. If this setting is used, the host
MCU should not alter the configuration of Register pd_aux, Field
extpa_bias_en.
PA Ramping Controller
The PA ramping controller of the ADF7242 minimizes spectral
splatter generated by the transmitter. Upon entering the TX state,
the ramping controller automatically ramps the output power of
the PA from the minimum output power to the specified nominal
value. In packet mode, transmission of the packet commences
after the ramping phase. When the transmission of the packet is
complete or the TX state is exited, the PA is turned off immedi-
ately. It is also possible to allow the PA to ramp down its output
power using the same ramp rate for the ramp-up phase, by
setting Register ext_ctrl, Field pa_shutdown_mode to 1.
The function of the two pins, PAVSUP_ATB3 and PABIAOP_
ATB4, depends on the mode selected with Register extpa_msc,
Field extpa_bias_mode, as shown in Table 26.
The reference current source for the DAC is controlled with
Register extpa_msc, Field extpa_bias_src (0x3AA[3]). If
Register extpa_msc, Field extpa_bias_src = 0, the current is
derived from the external bias resistor. If Register extpa_msc,
Field extpa_bias_src = 1, the current is derived from the
internal reference generator. The first option is more accurate
and is recommended whenever possible.
Figure 80 illustrates the shape of the PA ramping profile and its
timing. It follows a linear-in-dB shape. The ramp time depends on
the output power setting in Register extpa_msc, Field pa_pwr
and is specified with Register pa_rr, Field pa_ramp_rate
according to the following equation:
t_ramp = 2pa_rr.pa_ramp_rate × 2.4 ns × extpa_msc.pa_pwr
PA OUTPUT
POWER
TRANSMISSION OF
PACKET COMPLETE
OR LEAVING TX STATE
pa_ramp_rate = 0:
× 2.4ns PER 2dB STEP
pa_ramp_rate = 7:
2 × 2.4ns PER 2dB STEP
0
7
2
RC_TX
ISSUED
2dB
DATA
TRANSMISSION
ACTIVE
t
P
, MIN
O
tx_mac_delay + mac_delay_ext
Figure 80. PA Ramping Profile
Rev. 0 | Page 46 of 108
ADF7242
reference current. The reference current for the bias servo
loop is generated by the 5-bit reference DAC. In this mode,
the bias servo loop expects the current in the FET to increase
with increasing voltage at the PABIAOP_ATB4 output.
Mode 6 is the same as Mode 5, except that the bias servo
loop expects the current in the FET to increase with
decreasing voltage at the PABIAOP_ATB4 output.
External PA Interface Modes
Mode 0 allows supply to an external circuit to be switched
on or off. This is useful for circuits that have no dedicated
power-down pin and/or have a high power-down current.
Mode 1 allows the supply to an external circuit to be switched
on or off. In addition, the PABIOP_ATB4 pin acts as a
programmable current source. A programmable voltage
can be generated if a suitable resistor is connected between
PABIAOP_ATB4 and GND.
RFIO1P
LNA
BALUN
RFIO1N
Mode 2 allows the supply to an external PA circuit to be
switched on or off. In addition, the PABIOP_ATB4 pin acts
as a programmable current sink. A programmable voltage
can be generated if a suitable resistor is connected between
PABIAOP_ATB4 and VDD_BAT.
VDD_BAT
PAVSUP_ATB3
PABIAOP_ATB4
EXTERNAL PA
INTERFACE
CIRCUIT
PA
Mode 3 is the same as Mode 1, except that the switch
between PAVSUP_ATB3 and VDD_BAT is open.
Mode 4 is the same as Mode 2, except that the switch
between PAVSUP_ATB3 and VDD_BAT is open.
Mode 5 is intended for a PA circuit based on a single
external FET. The supply voltage to this FET is controlled
through the PAVSUP_ATB3 pin to ensure a low leakage
current in the power-down state. The bias servo loop
controls the gate bias voltage of the external FET such that
the current through the supply switch is equal to a
RFIO2P
LNA
BALUN
RFIO2N
TXEN_GP5
ADF7242
GaAs
pHEMT FET
Figure 81. Typical External PA Applications Circuit
Table 26. PA Interface
Register extpa_msc,
Field extpa_bias_mode
Register pd_aux,
Bit extpa_bias_en1
VDD_BAT to PAVSUP_ATB3 Switch
Function of Pin PABIAOP_ATB4
X2
0
1
2
3
4
5
6
7
0
1
1
1
1
1
1
1
1
Open
Not used
Not used
Current source
Current sink
Current source
Current sink
Bias current servo output, positive polarity
Bias current servo output, negative polarity
Reserved
Closed
Closed
Closed
Open
Open
Closed
Closed
Reserved
1 Autoenabled when Register ext_ctrl, Field extpa_auto_en = 1.
2 X = don’t care.
REGISTER ext_ctrl, FIELD extpa_auto_en
state == TX
ADF7242
&
VDD_BAT
REGISTER pd_aux, FIELD extpa_bias_en
SWITCH
3
5
PAVSUP_ATB3
CONTROL
LOGIC
REGISTER extpa_msc, FIELD extpa_bias_mode
PABIAOP_ATB4
DAC
REGISTER extpa_cfg, FIELD extpa_bias
REGISTER extpa_msc, FIELD extpa_bias_src
Figure 82. Details of External PA Interface circuit
Rev. 0 | Page 47 of 108
ADF7242
RECEIVER
receive and transmit in IEEE 802.15.4-2006 mode. The
requirements are as follows:
RECEIVE OPERATING MODES
The four primary receiver operating modes are
•
The value must not be a repeated symbol (for example, not
0x11 or 0x22).
The value must not be similar to the preamble symbol (that
is, not Symbol 0x0 or Symbol 0x8).
•
•
•
•
IEEE 802.15.4-2006 packet manager mode
IEEE 802.15.4-2006 SPORT mode
GFSK/FSK packet manager mode
GFSK/FSK SPORT mode
•
IEEE 802.15.4-2006 Receiver Configuration in Packet
Mode
The desired operating mode is selected with Register rc_cfg,
Field rc_mode. The SPORT modes are explained in more detail
in the SPORT Interface section.
IEEE 802.15.4-2006 mode with packet management support is
selected when Register rc_cfg, Field rc_mode = 0 (0x13E[7:0]).
RX_BUFFER is overwritten when the ADF7242 enters the RX
state following an RC_RX command and an SFD is detected. The
SFD is stripped off the incoming frame, and all data following
and including the frame length (PHR) is written to RX_BUFFER.
The data rate is set with Register dr0, Field data_rate_high and
Register dr1, Field data_rate_low as documented in the
Transmitter section. The data rate is automatically configured in
IEEE 802.15.4-2006 mode.
RECEIVER IN IEEE 802.15.4-2006 MODE
IEEE 802.15.4-2006 Reception
If Register pkt_cfg, Field auto_fcs_off = 1, the FCS of the incoming
frame is stored in RX_BUFFER. When the entire frame has been
received, an rx_pkt_rcvd interrupt is asserted irrespective of the
correctness of the FCS. If auto_fcs_off = 0, the radio controller
calculates the FCS of the incoming frame according to the FCS
polynomial defined in the IEEE 802.15.4-2006 standard (see
Equation 1), and compares the result against the FCS of the
incoming frame. An rx_pkt_rcvd interrupt is asserted only if
both FCS fields match. The FCS is not written to RX_BUFFER
but is replaced with the measured RSSI and signal quality
indicator (SQI ) values of the received frame (see Figure 83).
When IEEE 802.15.4-2006 mode is selected, the output of
the post demodulator filter is fed into a bank of correlators,
which compare the incoming data sequences to the expected
IEEE 802.15.4-2006 sequences. The IEEE 802.15.4-2006
receiver block operates in three primary states.
•
•
•
Preamble qualification
Symbol timing recovery
Data symbol reception
G16(x) = x16 + x12 + x5 +1
During preamble qualification, the correlators check for the pres-
ence of preamble. When preamble is qualified, the device enters
symbol timing recovery mode. The device symbol timing is
achieved once a valid SFD is detected. The ADF7242 supports
programmable SFDs. Refer to the IEEE 802.15.4-2006
Programmable SFD section for further details.
(1)
The behavior of the radio controller following the reception
of a frame can be configured with Register buffercfg, Field rx_
buffer_mode (0x107[1:0]). With the default setting rx_buffer_
mode = 0, the part reverts automatically to PHY_RDY when an
rx_pkt_rcvd interrupt condition occurs. This mode prevents
RX_BUFFER from being overwritten by the next frame before
the host MCU can read it from the ADF7242. This is because a
new frame is always written to RX_BUFFER starting from the
address stored in Register rxpb, Field rx_pkt_base (0x315[7:0]).
Note that reception of the next frame is inhibited until the MAC
delay following an RC_RX command has elapsed.
The received symbols are then passed to the packet manager in
packet mode or the SPORT interface in SPORT mode. In SPORT
mode, four serial clocks are output on Pin TRCLK_CKO_GP3,
and four data bits are shifted out on Pin DR_GP0 for each
received symbol. Refer to the SPORT Interface section for
further details.
If in packet mode, when the packet manager determines the end
of a packet, the ADF7242 automatically transitions to PHY_
RDY or TX or remains in RX, depending on the setting in
Register buffercfg, Field rx_buffer_mode (see IEEE 802.15.4-
2006 Receiver Configuration in Packet Mode section). If in
SPORT mode, the part remains in RX until the user issues a
command to change to another state.
If Register buffercfg, Field rx_buffer_mode = 1 (0x107[1:0]),
the part remains in the RX state, and the reception of the next
packet is enabled one MAC delay period after the frame has
been written to RX_BUFFER. Depending on the network setup,
this mode can cause an unnoticed violation of RX_BUFFER
integrity if a frame arrives prior to the MCU having read the
frame from RX_BUFFER.
IEEE 802.15.4-2006 Programmable SFD
If Register buffercfg, Field rx_buffer_mode = 2 (0x107[1:0]),
the reception of frames is disabled. This mode is useful for RSSI
measurements and CCA, if the contents of RX_BUFFER are to
be preserved.
An alternative to the standard IEEE 802.15.4-2006 SFD byte can
optionally be selected by the user. The default setting of Register
sfd_15_4, Field sfd_symbol_1 and Field sfd_symbol_2 (0x3F4[7:0])
is the standard IEEE 802.15.4-2006 SFD. If the user programs
this register with an alternative value, this is used as the SFD in
Rev. 0 | Page 48 of 108
ADF7242
unchanged during transitions between the PHY_RDY, RX, and
TX states. The synthesizer settling phase is always required
because the PLL bandwidth is optimized differently for RX and
TX operation. The static offset correction phase (OCL_stat) and
dynamic offset correction phase (OCL_dyn) are also mandatory.
RECEIVER CALIBRATION
The receive path is calibrated each time an RC_RX command is
issued. Figure 84 outlines the synthesizer and receive path
calibration sequence and timing for the IEEE 802.15.4-2006
mode of operation. The calibration step VCO_cal is omitted by
setting Register vco_cal_cfg, Field skip_vco_cal = 15 (0x36F[3:0]),
which is an option if the value of ch_freq[23:0] remains
1
2
1
0 TO 20
n
2
ADDRESS
INFORMA-
TION
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 1
REGISTER txpb, FIELD rx_pkt_base
+ 5 + (0 to 20) + n
REGISTER rxpb, FIELD rx_pkt_base
1
2
1
0 TO 20
n
1
1
ADDRESS
INFORMA-
TION
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 0
REGISTER txpb, FIELD rx_pkt_base
+ 5 + (0 to 20) + n
REGISTER rxpb, FIELD rx_pkt_base
Figure 83. IEEE 802.15.4-2006 Packet Fields Stored by the Packet Manager in RX_BUFFER
0µs TO 1020µs
192µs
rx_mac_delay
mac_delay_ext
SYNTH
OCL
OCL
INIT
VCO_cal
52µs
SETTLING STATIC
DYNAMIC
18µs
53µs 10µs
55µs
SKIPPED IF
REGISTER vco_cal_cfg,
FIELD skip_vco_cal = 15
188µs
Figure 84. RX Path Calibration, IEEE 802.15.4-2006 Mode
Rev. 0 | Page 49 of 108
ADF7242
Figure 85 shows the timing sequence for IEEE 802.15.4-2006
packet mode. If IEEE 802.15.4-2006 SPORT mode is enabled,
the timing sequence is the same except that no rx_pkt_rcvd
interrupt is generated and no automatic transition into the
PHY_RDY state occurs.
IEEE 802.15.4-2006 RECEIVE TIMING AND CONTROL
The IEEE 802.15.4-2006 operating mode is configured with
Register rc_cfg, Field rc_mode = 0 (0x13E[7:0]) for packet
mode, and Register rc_cfg, Field rc_mode = 2 for IEEE 802.15.4
RX SPORT mode. See the SPORT Interface section for details
on the operation of the SPORT interface. By default, ADF7242
performs a synthesizer and a receiver path calibration imme-
diately after it receives an RC_RX command. The transition into
the RX state occurs after the receiver MAC delay has elapsed. The
total receiver MAC delay is determined by the sum of the delay
times configured in Register delaycfg0, Field rx_mac_delay
(0x109[7:0]) and Register delaycfg2, Field mac_delay_ext
(0x10B[7:0]). Register delaycfg0, Field rx_mac_delay (0x109[7:0])
is programmable in steps of 1 μs, whereas Register delaycfg2,
Field mac_delay_ext (0x10B[7:0]) is programmable in steps of 4
μs. For IEEE 802.15.4-2006 RX operation, Register delaycfg2,
Field mac_delay_ext is typically set to 0. It can, however, be
dynamically used to accurately align the RX slot timing.
When entering the RX state, if Register cca2, Field rx_auto_cca = 1
(0x106[1]), a CCA measurement is started. The radio controller
asserts a cca_complete interrupt when the CCA result is
available in the status word. Upon detection of the SFD, the
radio controller asserts an rx_sfd interrupt, which can be used
by the host MCU for synchronization purposes. By default, the
ADF7242 transitions into the PHY_RDY state when a valid
frame has been received into RX_BUFFER and, if enabled, an
rx_pkt_rcvd interrupt is asserted. This mechanism protects the
integrity of RX_BUFFER. The RX state can be exited at any
time by means of an appropriate radio controller command.
RECEIVED
PACKET
PREAMBLE
RX
SFD PHR
PSDU
RC_RX
PREVIOUS STATE
PHY_RDY
RC_STATUS
rx_mac_delay +
mac_delay_ext
OPERATION
RX CALIBRATION
SFD SEARCH
CCA
OPTIONAL
REGISTER irq_src1, FIELD cca_complete
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src1, FIELD rx_sfd
REGISTER irq_src1, FIELD rx_pkt_rcvd
Figure 85. RX Timing and Control (IEEE 802.15.4-2006 Packet Mode)
Rev. 0 | Page 50 of 108
ADF7242
CCA results repeatedly until a RC_PHY_RDY command is
CLEAR CHANNEL ASSESSMENT (CCA)
issued. This case is illustrated in Figure 87. The first cca_complete
interrupt occurs when the first CCA averaging window after the
RX MAC delay has elapsed. The transceiver then repeatedly
restarts the CCA averaging window each time a cca_complete
interrupt is asserted.
The CCA function of the ADF7242 complies with CCA Mode 1
as per IEEE 802.15.4-2006. It is also applicable for the GFSK/FSK
mode of operation.
A CCA can be specifically requested by means of an RC_CCA
command or automatically obtained when the transceiver enters
the RX state. In both cases, the start of the CCA averaging window
is defined by when the RC_CCA or RC_RX command is issued
and when the delay is configured in Register delaycfg0, Field rx_
mac_delay (0x109[7:0]) and Register delaycfg2, Field mac_delay_
ext (0x10B[7:0]). The CCA result is determined by comparing
Register cca1, Field cca_thres (0x105[7:0]) against the average
RSSI value measured throughout the CCA averaging window.
If the measured RSSI value is less than the threshold value config-
ured in Register cca1, Field cca_thres (0x105[7:0]), CCA_
RESULT in the status word is set; otherwise, it is reset. The
cca_complete interrupt is asserted when CCA_RESULT in the
status word is valid.
This configuration is useful for longer channel scans.
CCA_RESULT in the status word can be used to identify if
the configured CCA RSSI threshold value has been exceeded
during a CCA averaging period. Alternatively, the RSSI value in
Register rrb, Field rssi_readback can be read by the host MCU
after each cca_complete interrupt. As indicated in Figure 87, the
RSSI readback value holds the results of the previous RSSI
measurement cycle throughout the CCA averaging window and
is updated only shortly before the cca_complete interrupt is
asserted.
The RSSI averaging time is programmable with Register agc_
cfg5, Field rssi_avg_time (0x3B9[1:0]) according to Table 113.
While operating the transceiver in IEEE 802.15.4-2006 mode,
setting Register agc_cfg5, Field rssi_avg_time = 2 (0x3B9[1:0]) is
required for compatibility.
Figure 86 shows the timing sequence after issuing the RC_CCA
command when Register cca2, Field continuous_cca = 0
(0x106[2]). Following the RC_CCA command, the transceiver
starts the CCA observation window after the delay specified by
the sum of Register delaycfg0, Field rx_mac_delay (0x109[7:0])
and Register delaycfg2, field mac_delay_ext (0x10b[7:0]) has
elapsed. A cca_complete interrupt is asserted at the end of the
CCA averaging window, and the transceiver enters the
PHY_RDY state.
Table 27. RSSI Averaging Time
Register agc_cfg5, Field rssi_avg_time
(0x3B9[1:0])
CCA Averaging
Period
0
1
2
3
16 μs
32 μs
64 μs
128 μs
When Register cca2, Field continuous_cca = 1 (0x106[2]), the
transceiver remains in CCA state and continues to calculate
RC_CCA
PHY_RDY
CCA
PHY_RDY
RC_STATUS
rx_mac_delay +
mac_delay_ext
OPERATION
RX CALIBRATION
CCA
REGISTER irq_src1, FIELD cca_complete
REGISTER irq_src0, FIELD rc_ready
Figure 86. CCA Timing Sequence, Register cca2, Bit continuous_cca = 0 (0x106[2])
RC_CCA
RC_PHY_RDY
PHY_RDY
CCA
PHY_RDY
RC_STATUS
rx_mac_delay +
mac_delay_ext
OPERATION
RX CALIBRATION
CCA1 CCA2
RSSI1 RSSI2
CCAn
REGISTER rrb, FIELD rssi_readback
X
RSSIn
REGISTER irq_src1, FIELD cca_complete
REGISTER irq_src0, FIELD rc_ready
Figure 87. CCA Timing Sequence, Register cca2, Bit continuous_cca = 1 (0x106[2])
Rev. 0 | Page 51 of 108
ADF7242
contains an 8-bit value representing the quality of a received
IEEE 802.15.4-2006 frame. It increases monotonically with the
signal quality and must be scaled to comply with the IEEE
802.15.4-2006 standard.
LINK QUALITY INDICATION (LQI)
The link quality indication (LQI) is defined in the IEEE 802.15.4-
2006 standard as a measure of the signal strength and signal quality
of a received IEEE 802.15.4-2006 frame. The ADF7242 makes
several measurements available from which an IEEE 802.15.4-2006-
compliant LQI value can be calculated in the MCU. The first
parameter is the RSSI value (see the Automatic Gain Control
(AGC) and Receive Signal Strength Indicator (RSSI) subsection
of the Receiver Radio Blocks section).
If the ADF7242 is operating in IEEE 802.15.4-2006 packet mode
(Register rc_cfg, Field rc_mode = 0 (0x13E[7:0])), and Register
pkt_cfg, Bit auto_fcs_off = 0 (0x108[0]), the SQI of a received
frame is measured and stored together with the frame in
RX_BUFFER. The SQI is measured over the entire packet and
stored in place of the second byte of the FCS of the received
frame in RX_BUFFER.
The second parameter required for the LQI calculation can be
read from Register lrb, Field sqi_readback (0x30D[7:0]), which
Rev. 0 | Page 52 of 108
ADF7242
Frame Filtering
IEEE 802.15.4 AUTOMATIC TX-TO-RX
TURNAROUND MODE
Frame filtering is available when the ADF7242 operates in IEEE
802.15.4 packet mode. The frame filtering function rejects
received frames not intended for the wireless node. The filtering
procedure is a superset of the procedure described in Section
7.5.6.2 (third filtering level) of the IEEE 802.15.4-2006 standard.
Field addon_en in Register pkt_cfg controls whether frame
filtering is enabled
The ADF7242 features an automatic TX-to-RX turnaround
mode when operating in IEEE 802.15.4-2006 packet mode. The
automatic TX-to-RX turnaround mode facilitates the timely
reception of acknowledgment frames.
Figure 88 illustrates the timing of the automatic TX-to-RX
turnaround mode. When enabled by setting Register buffercfg,
Field auto_tx_to_rx_turnaround (0x107[3]), the ADF7242
automatically enters the RX state following the transmission of
an IEEE 802.15.4-2006 frame. After the combined receiver
MAC delay (Register delaycfg0, Field rx_mac_delay + Register
delaycfg2, Field mac_delay_ext), the ADF7242 enters the RX
state and is ready to receive a frame into RX_BUFFER.
Subsequently, when a valid IEEE 802.15.4-2006 frame is
received, the ADF7242 enters the PHY_RDY state.
Automatic Acknowledgment
The ADF7242 has a feature that enables the automatic transmis-
sion of acknowledgment frames after successfully receiving a
frame. The automatic acknowledgment feature of the receiver
can only be used in conjunction with the IEEE 802.15.4 frame
filtering feature. When enabled, an acknowledgment frame is
automatically transmitted when the following conditions are
met:
IEEE 802.15.4 FRAME FILTERING, AUTOMATIC
ACKNOWLEDGE, AND AUTOMATIC CSMA/CA
•
•
•
The received frame is accepted by the frame filtering
procedure.
The received frame is not a beacon or acknowledgment
frame.
The acknowledgment request bit is set in the FCF of the
received frame.
The following IEEE 802.15.4-2006 functions are enabled by the
firmware module, RCCM_IEEEX:
•
•
Automatic IEEE 802.15.4 frame filtering
Automatic acknowledgment of received valid IEEE
802.15.4 frames
•
Automatic frame transmission using unslotted CSMA/CA
with automatic retries
See the Downloadable Firmware Modules and Writing to the
ADF7242 sections for details on how to download a firmware
module to the ADF7242.
PACKET TRANSMITTED
PACKET RECEIVED
FRAME IN TX_BUFFER
VALID IEEE802.15.4-2006 FRAME
TX
RX
PHY-RDY
RC_STATUS
rx_mac_delay +
mac_delay_ext
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src1, FIELD rx_pkt_rcvd
REGISTER irq_src1, FIELD rx_pkt_sent
Figure 88. IEEE 802.15.4-2006 Auto TX-to-RX Turnaround Mode
Rev. 0 | Page 53 of 108
ADF7242
Figure 89 shows the format of the acknowledgment frame
assembled by the ADF7242. The sequence number (Seq. Num.)
is copied from the frame stored in RX_BUFFER. The automatic
acknowledgment feature of the receiver uses TX_BUFFER to
store the constructed acknowledgment frame prior to its
transmission. Any data present in TX_BUFFER is overwritten
by the acknowledgment frame prior to its transmission.
of the frame to commence immediately after the MAC delay has
expired. This configuration facilitates the implementation of the
transmit procedure in networks using slotted CSMA/CA. In this
case, the timing of the CCA operation must be controlled by the
host MCU, and the number of retries must be set to 1.
Prior to the transmission of the frame stored in TX_BUFFER the
radio controller checks if the acknowledge request bit in the
FCF of that frame is set. If it is set, then an acknowledgment
frame is expected following the transmission. Otherwise, the
transaction is complete after the frame has been transmitted.
The acknowledgment request bit is Bit 5 of the byte located at
the address contained in Register txpb, Field tx_packet_base + 1.
4
1
1
2
1
2
PREAMBLE
Figure 89. ACK Frame Format
The transmission of the ACK frame starts after the combined
delay given by the sum of the delays specified in Register
delaycfg1, Field tx_mac_delay and Register delay_cfg2, Field
mac_delay_ext has elapsed. The default settings of Register
delaycfg1, Field tx_mac_delay = 192 and Register delay_cfg2,
Field mac_delay_ext = 0 result in a delay of 192 μs, which suits
networks using unslotted CSMA/CA. Optionally, Register
delay_cfg2, Field mac_delay_ext can be updated dynamically
while the delay specified in Register delaycfg1, Field
Figure 90 depicts the automatic CSMA/CA operation. The
firmware module download enables an additional command,
RC_CSMACA, to initiate this CSMA/CA operation. It also
enables an additional interrupt, csma_ca_complete, to be set to
indicate when the CSMA/CA procedure is completed. As per
the IEEE 802.15.4-2006 standard for unslotted CSMA/CA, the
first CCA is delayed by a random number of backoff periods,
where a unit backoff period is 320 μs. The CCA is carried out
for a period of 128 μs as specified in the IEEE 802.15.4-2006
standard.
tx_mac_delay elapses. This option enables accurate alignment
of the acknowledgment frame with the back-off slot boundaries
in networks using slotted CSMA/CA.
If a busy channel is detected during the CCA phase, the radio
controller performs the next delay/CCA cycle until the maxi-
mum number of CCA retries specified has been reached. If the
maximum number of allowed CCA retries has been reached,
the operation is aborted and the device transitions to the
PHY_RDY state.
When the receiver automatic acknowledgment mode is enabled,
the ADF7242 remains in the RX state until a valid frame has
been received. When enabled, an rx_pkt_rcvd interrupt is
generated. The ADF7242 then automatically enters the TX state
until the transmission of the acknowledgment frame is
complete. When enabled, a tx_pkt_sent interrupt is generated to
signal the end of the transmission phase. Subsequently, the
ADF7242 returns to the PHY_RDY state.
If the CCA was successful, the radio controller changes the
device state from the CCA state to the TX state and transmits
the frame stored in TX_BUFFER. The minimum turnaround
time from RX to TX is 106 μs. If neither the acknowledge
request bit in the transmitted frame nor the csma_ca_turnaround
bit are set, the device returns to the PHY_RDY state immedi-
ately upon completion of the frame transmission. Otherwise, it
enters the RX state and waits for up to 864 μs for an acknowledg-
ment. If an acknowledgment is not received within this time
and the maximum number of frame retries has not been reached,
the ADF7242 remains inside the frame transmit retry loop
and starts the next CSMA/CA cycle. Otherwise, it exits to the
PHY_RDY state. The procedure exits with a csma_ca_complete
interrupt.
Automatic Unslotted CSMA/CA Transmit Operation
The automatic CSMA/CA transmit operation automatically
performs all necessary steps to transmit frames in accordance
with the IEEE 802.15.4-2006 standard for unslotted CSMA/CA
network operation. It includes automatic CCA retries with
random backoff, frame transmission, reception of the
acknowledgment frame, and automatic retries in the case of
transmission failure. Partial support is provided for slotted
CSMA/CA operation.
The number of CSMA/CA CCA retries can be specified
between 0 and 5 in accordance with the IEEE 802.15.4 standard.
The CSMA/CA can also be disabled, causing the transmission
Rev. 0 | Page 54 of 108
ADF7242
FRAME Tx RETRY LOOP
OPTION TO SKIP FOR
SLOTTED CSMA/CA
SKIPPED IF
ACK REQUEST BIT IS NOT SET
CSMA-CA PHASE
ACK Rx PHASE
RC_CSMACA
COMMAND
FRAME
TRANSMIT
RECEIVE
ACK
CCA
BE
rx_mac_delay
rnd(2 – 1)
192µs (def)
320µs
128µs
106µs
192µs
<864µs
RX
STATE
PREVIOUS STATE
CCA
Tx
PHY_RDY
csma_ca_complete
Figure 90. Automatic CSMA/CA Transmit Operation (with CCA)
Rev. 0 | Page 55 of 108
ADF7242
If fsk_preamble_match level is set to 0x0C, the ADF7242 must
receive 12 consecutive b10 pairs (three bytes) to confirm valid
preamble has been detected. Then, the preamble level must be
maintained equal or above the detection threshold over a
number of bytes to obtain full qualification. If the number of
erroneous bit-pairs drops below the detection threshold before
the end of the qualification time; the packet manager discards
the preamble and restarts the detection.
RECEIVER IN GFSK/FSK MODE
The packet manager can detect and interrupt the host MCU
upon receiving a qualified preamble, sync word, or valid FCS.
The packet manager then stores the received data payload in the
packet RAM. This section describes the various configurations
of the packet manager in receive mode.
GFSK/FSK Packet Mode Reception
To configure GFSK/FSK packet mode, set Register rc_cfg, Field
rc_mode = 4 (0x13E[7:0])). Register writes required to confi-
gure GFSK/FSK SPORT are given in the SPORT Interface
section. Table 29 shows the fields applicable to GFSK/FSK
packet reception, and Figure 91 shows which fields are stored by
the packet manager in RX_BUFFER.
The number of preamble bytes required for qualification can be
set by Register preamble_num_validate (0x3F3). The user can
select the option to automatically lock the AFC and/or AGC at
this point. The lock AFC on preamble qualification can be
enabled by setting Register afc_config, Field afc_lock_mode =
0x3 (0x3F7[1:0]). The lock AGC on preamble detection can be
enabled by setting Register fsk_preamble_config, Field fsk_agc_
lock_after_preamble to 1 (0x111[5]).
Preamble
This is a mandatory part of the packet that is automatically
removed after receiving a packet. In receive mode, the preamble
detection circuit tracks the received frame as a sliding window.
The window is three bytes in length, and the preamble pattern is
fixed at 0xAA. The preamble bits are examined in 2-bit pairs
(for example, b10). If either or both bits are in error, the pair is
deemed erroneous. The possible erroneous pairs are b00, b11,
and b01. The number of erroneous pairs tolerated in the
preamble detection can be set by Register fsk_preamble_config,
Field fsk_preamble_match_level, as shown in Table 28.
Table 28. Preamble Detection Tolerance
(Register fsk_preamble_config, Location 0x111)
Value
0x0C
0x0B
0x0A
0x09
0x08
0x00
Description
0 errors allowed
1 erroneous bit-pair allowed in 12 bit-pairs
2 erroneous bit-pairs allowed in 12 bit-pairs
3 erroneous bit-pairs allowed in 12 bit-pairs
4 erroneous bit-pairs allowed in 12 bit-pairs
Preamble detection disabled
Table 29. Description of Fields Applicable to GFSK/FSK Packet Reception
Packet Structure
Payload
Field
Preamble
No
SWD
Yes
Length
N/A
Payload Data
CRC
Yes
Postamble
N/A
Receive Interrupt on Valid Field Detection
Programmable Field Error Tolerance in RX
N/A
N/A
Yes
Yes
N/A
N/A
N/A
n = 1 TO 252
2
2
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 0
REGISTER rxpb, FIELD rx_pkt_base
REGISTER rxpb, FIELD rx_pkt_base
2 + n
REGISTER rc_cfg, FIELD rc_mode = 4
n = 1 TO 254
2
FRAME
PAYLOAD
REGISTER pkt_cfg, FIELD auto_fcs_off = 1
REGISTER rxpb, FIELD rx_pkt_base
Figure 91. GFSK/FSK Packet Fields stored by the Packet Manager in RX_BUFFER
Rev. 0 | Page 56 of 108
ADF7242
When preamble has been qualified, the packet manager
searches for a sync word. From the end of preamble, the chip
processor searches for the sync word for a maximum duration
of four bytes. This is illustrated in Figure 92. If sync word is
detected during this window, the packet manager stores the
received payload to packet RAM and computes the CRC (if
enabled). If the sync word is not detected during this duration,
the packet manager unlocks the AGC/AFC and then returns to
searching for preamble.
The ADF7242 can provide an interrupt on reception of the
programmed sync word. This feature can be used to alert the
host microprocessor that a valid packet has been received. An
error tolerance parameter can also be programmed that accepts
a valid match when up to three bits of the sync word sequence
are incorrect. The error tolerance value is set using the sync_tol
setting in Register sync_config (0x10F[6:5]) as described in
Table 30. On reception of a valid sync word, the chip processor
automatically writes the receive payload to the packet RAM.
The rx_pkt_base value in Register rxpb sets the location in
packet RAM of the first byte of the received payload. For more
details on packet RAM, refer to the Memory Map section.
Preamble detection can be disabled by setting Register fsk_
preamble_config, Field skip_preamble_detect_qual high
(Location 0x111).
Table 30. Sync Word Detection Tolerance (sync_config,
Register 0x10F)
SEARCH FOR PREAMBLE
PREAMBLE DETECTED
Value
Description
00
01
10
11
0 bit errors allowed
1 bit error allowed
2 bit errors allowed
3 bit errors allowed
SEARCH FOR SYNC WORD
SEARCH DURATION (BITS)
NO SYNC WORD DETECTED
FROM END OF PREAMBLE =
DURING SEARCH DURATION
SYNC_WORD_LENGTH + 16 BITS +
PREAMBLE ERROR TOLERANCE (BITS)
CRC
SYNC WORD DETECTED
DURING SEARCH DURATION
To enable CRC detection on the receiver with the 16-bit CRC
described in the Transmitter in GFSK/FSK Mode section, set
Register pkt_cfg, Field auto_fcs_off = 0 (0x108[0]). This is the
default setting. An interrupt on reception of a valid packet
containing the correct CRC can be enabled by setting the
rx_pkt_rcvd interrupt in Register irq1_en1 or Register irq2_en1.
PROCESS PAYLOAD
Figure 92. Search for Preamble and Search for Sync Word Routine
By the Packet Manager
Sync Word (SWD)
This is the synchronization word that is used by the receiver for
byte-level synchronization, while also providing an optional
interrupt on detection. It is automatically removed after
receiving a packet.
If it is desired to receive a packet that has a CRC word generated
by a different CRC formula, the host MCU should set Register
pkt_cfg, Field auto_fcs_off = 1. The CRC word received is
stored in RX_BUFFER, as shown in Figure 91. An rx_pkt_rcvd
interrupt is not generated; therefore, it is recommended that an
rx_sfd interrupt be enabled to inform the host MCU when a
packet has been received. Refer to the Interrupt Controller
section for details.
The value of the SWD is set in the sync_word0, sync_word1,
and sync_word2 registers (0x10C, 0x10D, and 0x10E). The
SWD is transmitted most significant bit first starting with
sync_word2. The SWD matching length at the receiver is set
using Register sync_config, Field sync_len (0x10F[4:0]) and can
be one bit to 24 bits in length.
Rev. 0 | Page 57 of 108
ADF7242
Receive GFSK/FSK Demodulator
with low data rates, the frequency error between the local
oscillator of the transmitter and receiver can be a significant
fraction of the deviation frequency. This frequency error must
be considered when optimizing the demodulator bandwidth
setting to ensure reliable operation. The discriminator band-
width setting is set by Register dm_cfg0, Field discriminator_bw
(0x305[6:0]). The discriminator bandwidth setting can be
calculated from
Figure 93 shows a block diagram of the receive demodulator. A
correlator demodulator is used for 2FSK and GFSK demodula-
tion. The quadrature outputs of the analog baseband filter are
digitized and then fed to a digital frequency correlator that
performs filtering and frequency discrimination of the FSK or
GFSK signal.
For GFSK/FSK demodulation, data is recovered by comparing
the output levels from two correlators. The performance of this
frequency discriminator approximates that of a matched filter
detector, which is known to provide optimum detection in the
presence of additive white Gaussian noise (AWGN). This method
of GFSK/FSK demodulation provides approximately 3 dB to
4 dB better sensitivity than a linear demodulator.
3.25 MHz
discriminator _ bw[6 : 0] =
FSK _ dev + freq _ error _ max
where:
FSK_dev is the GFSK/FSK frequency deviation in Hz (measured
from the RF carrier to the Logic 0 or Logic 1 frequency).
freq_error_max is the maximum expected frequency error, in
hertz (Hz), between the carrier frequency of the transmitted
signal and the local oscillator (LO) frequency of the receiver.
The correlator demodulator bandwidth must be configured with
Register dm_cfg0, Field discriminator_bw (0x305[6:0]) to match
the deviation frequency of the received signal. For applications
SPORT MODE
GPIOs
ADC
CLOCK
AND DATA
PREAMBLE
DETECT
CORRELATOR
DEMODULATOR
ADC
SYNCWORD
DETECT
REGISTER iirf_cfg, FIELD iir_stage1_bw
REGISTER dm_cfg0,
PACKET MANAGER
FIELD discriminator_bw
REGISTER iirf_cfg, FIELD iir_stage2_bw
REGISTER dr0, FIELD data_rate_high
REGISTER dr1, FIELD data_rate_low
REGISTER dm_cfg1,
FIELD postdemod_bw
AFC SYSTEM
T
2
RF
SYNTHESIZER
(LO)
RANGE
AVERAGING
FILTER
PI
CONTROL
afc_range
afc_cfg
REGISTER afc_ki_kp, FIELD afc_ki
REGISTER afc_ki_kp, FIELD afc_kp
Figure 93. Structure of RX Demodulator
Rev. 0 | Page 58 of 108
ADF7242
Automatic Frequency Correction (AFC)
Postdemodulator Filter
A shown in Figure 93, the ADF7242 is equipped with a fully
automatic real-time AFC function. It is used to maintain an
optimal link budget in the presence of frequency errors between
the local oscillators of the receiver and transmitter. AFC is sup-
ported in GFSK/FSK mode only.
The digital post demodulator filter, shown in Figure 93,
removes excess noise from the demodulator output. Its
bandwidth is programmable with Register dm_cfg1, Field
postdemod_bw (0x38B[7:0]) and should be optimized for the
data rate used. If the bandwidth is set too narrow, performance
degrades due to intersymbol interference. If the bandwidth is
set too wide, performance degrades due to excess noise. For
optimum performance, the post demodulator filter bandwidth
should be set to 0.75 × data rate. The following formula can be used
to determine the appropriate register setting:
When AFC is enabled, an internal control loop automatically
monitors the frequency error during the preamble sequence of
the packet and adjusts the synthesizer LO using an internal
proportional integral (PI) control loop. The AFC frequency
error measurement bandwidth is targeted specifically at the
packet preamble sequence (dc free). When preamble is detected,
the AFC is locked by the radio controller. AFC lock is released if
the sync word is not detected immediately after the end of
preamble. This can be due to false lock, poor quality preamble,
and/or sync word. If the qualified preamble is followed by a
qualified sync word, the AFC lock is maintained for the
duration of the packet.
postdemod_bw = roundoff(17 × 10−5 × (0.75 ×
data rate[bps]) − 4 × 10−11(0.75 × data rate[bps])2)
Refer to the Device Configuration section for recommended
postdemodulator filter settings and for example data rates.
Clock and Data Recovery (CDR)
An oversampled digital clock and data recovery (CDR) PLL is
used to resynchronize the received bit stream to a local clock in all
modulation modes. The data rate of the CDR is set by Register
dr0, Field data_rate_high (0x30E[7:0]) and Register dr1, Field
data_rate_low (0x30F[7:0]).
Setting Register afc_cfg, Field afc_mode = 3 (0x3F7[1:0]) enables
AFC operation with automatic preamble locking, which is the
recommended setting. The frequency error readback word in
Register afc_read, Field afc_freq_error (0x3FA[7:0]) is conti-
nuously updated until the AFC is locked. The frequency correction
is maintained if the ADF7242 transitions to another state (such
as TX). It is overwritten with a new frequency correction value
when the receiver next detects valid preamble, or it can be cleared
by setting Register afc_range, Field max_afc_range = 0 and
Register afc_cfg, Field afc_mode = 2.
The maximum data rate tolerance of the CDR PLL is deter-
mined by the number of bit transitions in the transmitted
packet. For example, if using GFSK/FSK with a 101010…
preamble, a maximum tolerance of 3.0ꢀ of the data rate is
achieved.
This tolerance is reduced during the recovery of the remainder
of the packet where data transitions may not occur on regular
intervals.
The recommended settings for the AFC control loop parameters
are Register afc_ki_kp, Field afc_ki = 9 and Register afc_ki_kp,
Field afc_kp = 9. An example of AFC performance for a
selection of data rates is given in Table 31.
However, it is possible to tolerate uncoded payload data fields
and payload data fields with long run length coding constraints
if the data rate tolerance and packet length are both con-
strained. More details of CDR operation using uncoded packet
formats are described in the AN-915 Application Note.
The maximum AFC correction range is set by Register afc_range,
Field max_afc_range. It has a resolution of 1 kHz. This setting
helps prevent the AFC loop from attempting to acquire signals
outside the frequency range of interest. The AFC detects and
corrects frequency errors up to max_afc_range from the pro-
grammed channel frequency. The nominal channel frequency is set
by the frequency control word, ch_freq[23:0]. The max_afc_range
value is generally set to less than half the bandwidth of the
baseband filter.
The CDR is designed for fast acquisition of the recovered symbols
during the preamble and typically achieves bit synchronization
within five symbol transitions of preamble.
Table 31. Example AFC Performance
Parameter
2000 kbps, fDEV = 500 kHz
500 kbps, fDEV = 250 kHz
Preamble Length
11 bytes
165 kHz
80 kHz
7 bytes
190 kHz
80 kHz
90 kHz
Frequency Error Tolerance with AFC
Maximum AFC Correction Range
Frequency Error Tolerance Without AFC
55 kHz
Rev. 0 | Page 59 of 108
ADF7242
Receiver Calibration in GFSK/FSK Mode
GFSK/FSK Receive Timing and Control
The receive path is calibrated each time an RC_RX command is
issued. The sequence is identical for IEEE 802.15.4 and
GFSK/FSK mode of operation; the timing parameters, however,
are different. Figure 94 outlines the synthesizer and receive path
calibration sequence and timing for the GFSK/FSK mode of
operation. (See the Receiver Calibration section for information
on which calibration stages are mandatory and which are optional.)
GFSK/FSK receive mode is enabled by setting Register rc_cfg, Field
rc_mode = 3 (0x13E[7:0]). See the SPORT Interface section for
details. Figure 95 shows the timing and control sequence for
GFSK/FSK SPORT mode. Figure 96 shows the timing and
control sequence for GFSK/FSK packet mode.
In order for the RC_READY interrupt to be generated at the
correct time, Register delaycfg2, Field mac_delay_ext must be
set to 0x76 (472 μs). If this value is set, the total MAC delay in
GFSK/FSK receive mode is 664 μs. For applications requiring
fast turnaround times, it is recommended that Register delaycfg2,
Field mac_delay_ext be set to 0x00. In this case, the RC_
READY interrupt should be ignored because the calibration
time is still 664 μs.
In GFSK/FSK reception, the total receiver calibration time is
664 μs. Assuming that Register delaycfg0, Field rx_mac_delay
(0x109[7:0]) remains at the default delay setting of 192 μs, this
requires Register delaycfg2, Field mac_delay_ext (0x10B[7:0])
to be set to 472 μs. Optimal receiver performance is achieved
when no input signal is present during the receiver MAC delay.
192µs
472µs TO 1020µs
Following the receiver MAC delay, the transceiver enters the RX
state. The transceiver starts to search for a valid preamble/sync
word. If enabled, an rx_sfd interrupt is asserted when a preamble
followed by the correct sync word has been received. In GFSK/
FSK SPORT mode, the framing signal appearing on the IRQ2_
TRFS_GP2 output provides more accurate timing information
than the rx_sfd interrupt and no rx_pkt_rcvd interrupt is
generated. A command to enter an alternative state must be
issued to exit the RX state.
rx_mac_delay
mac_delay_ext
SYNTH
SETTLING STATIC
OCL
OCL
INIT VCO_cal
DYNAMIC
18µs
52µs
80µs
10µs
404µs
SKIPPED IF
REGISTER vco_cal_cfg,
FIELD skip_vco_cal = 15
664µs
Figure 94. Receive Path Calibration, GFSK/FSK Mode
RECEIVED
PACKET
PREAMBLE
RX
SFD PHR
PSDU
RC_RX
RC_PHY_RDY
PREVIOUS STATE
PHY_RDY
RC_STATUS
rx_mac_delay +
mac_delay_ext
OPERATION
RX CALIBRATION
SYNC SEARCH
REGISTER irq_src1, FIELD rx_sfd
REGISTER irq_src0, FIELD rc_ready
Figure 95. RX Timing and Control GFSK/FSK SPORT Mode
PREAMBLE SWD
PAYLOAD
POSTAMBLE
RECEIVED PACKET
RC_TX
RC_STATUS
PREVIOUS STATE
TX
PHY_RDY
FIELD rx_mac_delay +
mac_delay_extension
OPERATION
RX CALIBRATION
SWD SEARCH
REGISTER irq_src0, FIELD rc_ready
REGISTER irq_src0, FIELD rx_sfd
REGISTER irq_src0, FIELD rx_pkt_rcvd
Figure 96. RX Timing and Control GFSK/FSK Packet Mode
Rev. 0 | Page 60 of 108
ADF7242
Offset Correction Loop (OCL)
RECEIVER RADIO BLOCKS
The ADF7242 is equipped with a fast and autonomous offset
correction loop (OCL), which cancels both static and dynamic
time-varying offset voltages present in the zero-IF receiver path.
In IEEE 802.15.4 mode, the OCL operates continuously and is
not constrained by the formatting, timing, or synchronization
of the data being received. In GFSK/FSK mode, the OCL is
active only during the receive path calibration phase. After
minimizing the offset voltage, the OCL is automatically frozen
until the next RC_RX command is issued. This scheme allows
the ADF7242 to maintain its RF sensitivity independent of any
data formatting constraints in the GFSK/FSK mode. The
scheme is also suitable for fast hopping spread-spectrum (FHSS)
communication systems. However, because the offset voltages in
the receive path are subject to drift over time, there is an upper
limit on the channel dwell time. When operating in GFSK/FSK
mode, it is recommended to re-issue the RC_RX command at
least every 400 ms. It is recommended to use the values listed in
the Device Configuration section for the configuration registers
pertaining to the offset correction loop.
Baseband Filter
Baseband filtering on the ADF7242 is accomplished by a cascade of
analog and digital filters. The single-sided 3 dB bandwidth of the
analog baseband filter is programmable from 555 kHz to 1126 kHz
through Register rxfe_cfg, Field rxbb_bw_ana (0x39B[3:0]). The
bandwidth of the digital filter can be set with Register iirf_cfg,
Field iir_stage1_bw (0x389[1:0]) and Register iirf_cfg, Field
iir_stage2_bw (0x389[4:2]). The recommended settings for
these registers given in the Device Configuration section are
based on the modulation parameters shown in Table 22 in the
Transmitter section. These settings assume a crystal frequency
tolerance of 20 ppm for GFSK/FSK mode and 40 ppm for
IEEE 802.15.4-2006 mode. Any changes in Register rxfe_cfg,
Field rxbb_bw_ana take effect only upon transition from the idle
to the PHY_RDY state. Table 32 shows example bandwidths for
the analog and digital filters.
Table 32. Analog and Digital Filter Parameters
Analog Filter
Digital Filter
Register rxfe_cfg, Field
rxbb_bw_ana (0x39B[3:0])
One-Sided 3 dB
Bandwidth (kHz)
Register iirf_cfg, Field
iir_stage1_bw (0x389[1:0])
Register iirf_cfg, Field One-Sided 3 dB
iir_stage2_bw (0x389[4:2]). Bandwidth (kHz)
14
14
13
12
11
10
9
1126
1086
1029
991
927
867
2
2
2
2
3
4
480
320
260
797
8
730
7
655
6
555
Rev. 0 | Page 61 of 108
ADF7242
where
α = 2 + (Register agc_cfg5, Field agc_filt2_tavg1) +(Register
Automatic Gain Control (AGC) and Receive Signal
Strength Indicator (RSSI)
The ADF7242 AGC circuit features fast overload recovery using
dynamic bandwidth adjustments for fast preamble acquisition
and optimum utilization of the dynamic range of the receiver path.
The radio controller automatically enables the AGC after an
offset correction phase, which is carried out when the trans-
ceiver enters the RX state. The optimum AGC configuration
parameters depend on the selected data rate, the modulation
format, and the configuration of the receiver offset correction
loop. The recommended settings for the AGC configuration
registers based on the modulation parameters, shown in Table 22,
are given in the Device Configuration section.
agc_cfg6, Field agc_filt2_tavg2) + (Register agc_cfg5, Field
rssi_avg_time)
In IEEE 802.15.4-2006 mode, the default RSSI averaging period
of 128 μs, or eight symbol periods, must be used for compliance
with the IEEE 802.15.4-2006 standard. If the ADF7242 is
operating in the IEEE 802.15.4-2006 packet mode, the RSSI of
received frames is measured and stored together with the frame
in RX_BUFFER. The RSSI is measured in a window with a
length of eight symbols immediately following the detected
SFD. The result is then stored in place of the first byte of the
FCS of the received frame in RX_BUFFER. For GFSK/FSK
mode, the optimum RSSI averaging time is application dependent
and the default settings should be appropriate for most
applications.
In GFSK/FSK mode, it is possible to lock the AGC and prevent
further gain updates after the reception of the preamble using
Register fsk_preamble_config, Field fsk_agc_lock_after_
preamble.
It is also possible to compensate for systematic errors of the
measured RSSI value and/or production tolerances by adjusting
the RSSI readback value by an offset value that can be
programmed in Register agc_cfg5, Field rssi_offs (0x3B9[4:2]).
The adjustment resolution is in 1 dB steps.
The RSSI readback value is continuously updated while the
ADF7242 is in the RX state. The result is provided in Register
rrb, Field rssi_readback (0x30C[7:0]) in decibels relative to
1 mW (dBm) using signed twos complement notation. The
RSSI averaging window is synchronized with the start of the
active RX phase at the end of the MAC delay following an
RC_RX command. The RSSI averaging time is programmable
with Register agc_cfg5, Field rssi_avg_time (0x3B9[1:0]), and
depends on the AGC update rate according to the following
formula:
T_avg_rssi = 77 ns × 2α
Rev. 0 | Page 62 of 108
ADF7242
SPORT INTERFACE
The SPORT interface is a high speed synchronous serial interface
suitable for interfacing to a wide variety of MCUs and DSPs,
without the use of glue logic. These include, among others, the
ADSP-21xx, SHARC, TigerSHARC and Blackfin DSPs. Figure 116
and Figure 117 show typical application diagrams using one of
the available SPORT modes. The interface uses four signals, a clock
output (TRCLK_CKO_GP3), a receive data output (DR_GP0),
a transmit data input (DT_GP1), and a framing signal output
(IRQ2_TRFS_GP2). The IRQ2 output functionality is not
available while the SPORT interface is enabled. The SPORT
interface supports GFSK/FSK and IEEE 802.15.4 receive and
transmit operations. When using GFSK/FSK mode, the polarity of
the receive/transmit clock appearing on the TRCLK_CKO_GP3
output is programmable. A detailed overview of the function of
the interface pins for each GFSK/FSK mode SPORT configuration
is listed in Table 33. The corresponding list for IEEE 802.15.4
mode is listed in Table 34. It is possible to use the SPORT
interface for transmitting IEEE 802.15.4 frames by configuring
the ADF7242 in 2 Mbps FSK mode (see Device Configuration
section) and performing the symbol chipping operation
externally.
outlined in the GFSK/FSK Packet Mode Reception section,
prior to issuing the RC_RX command.
When in SPORT mode, received data continues to appear on
the interface pins until the RC_RX command is reissued or the
RX state is exited by means of an appropriate SPI command.
The following SPORT operating modes can be selected.
Register gp_cfg, Field gpio_config = 1 or
Field gpio_config = 4
The data clock is enabled at the TRCLK_CKO_GP3 output
together with the received data at the DR_GP0 output during
the receiver MAC delay. The GFSK/FSK SWD is ignored in this
configuration. The IRQ2_TRFS_GP2 output has no function.
Figure 10 illustrates further timing details.
Register gp_cfg, Field gpio_config = 2 or
Field gpio_config = 5
When a preamble signal has been detected, the data clock and
data signals start to appear at the TRCLK_CKO_GP3 and
DR_GP0 output, respectively. The IRQ2_TRFS_GP2 output
goes HIGH when the sync word has been detected in the
received GFSK/FSK bit stream. Figure 11 shows more timing
details.
GFSK/FSK SPORT MODE
GFSK/FSK SPORT Mode Transmit Operation
Register gp_cfg, Field gpio_config = 3 or
Field gpio_config = 6
Figure 97 illustrates the operation of the SPORT interface in the
TX state. The SPORT interface is enabled by setting Register
gp_cfg, Bit gpio_config = 1 or Bit gpio_config = 4 (0x32C[7:0])
depending on the desired clock polarity. When enabled, the
data input of the transmitter is fully controlled by the SPORT
interface. The transmit clock appears when the transmit MAC
delay (tx_max_delay) has elapsed. The ADF7242 keeps transmit-
ting the serial data presented at the DT_GP1 input until the TX
state is exited by means of a command, for example, the RC_
PHY_RDY command. A timing diagram GFSK/FSK transmit
SPORT mode is provided in Figure 13.
The data clock starts to appear at the TRCLK_CKO_GP3 output
when a valid preamble and the SWD have both been detected in
the received GFSK/FSK bit stream. The first active clock edge
corresponds with the first data bit following the GFSK/FSK
SWD appearing on the DR_GP0 output. The framing signal
IRQ2_TRFS_GP2 goes high when the SWD has been detected
in the received bit sequence. The DR_GP0 output signal should
be ignored prior to the first active clock edge appearing on the
TRCLK_CKO_GP3 output. Figure 12 illustrates the applicable
timing details.
GFSK/FSK SPORT Mode Receive Operation
SWD and Preamble in GFSK/FSK SPORT Mode
The SPORT interface supports GFSK/FSK receive operation
with a number of modes to suit particular signaling require-
ments, as shown in Figure 98. For GFSK/FSK receive SPORT
operation, set Register rc_cfg, Field rc_mode = 3 (0x13E[7:0]).
This disables any packet-level processing by the packet
manager. The operating mode of the SPORT interface can be
configured through Register gp_cfg, Bit gpio_config
(0x32C[7:0]). Table 33 shows an overview of all available
configurations. The SPORT mode configurations gpio_config =
2, 3, 5, and 6 in Register gp_cfg provide synchronization with a
programmable SWD. For these modes, the synchronization
block must be configured with appropriate register writes as
To configure GFSK/FSK SPORT mode, set Register rc_cfg, Field
rc_mode = 3 (0x13E[7:0]). The preamble length requirements
and tolerance options described in the GFSK/FSK Packet Mode
section also apply for SPORT mode. The ADF7242 can also
support automatic detection of a SWD in SPORT mode. The
ADF7242 SWD detection algorithm as described in the
GFSK/FSK Packet Mode Reception section applies. There are a
number of clock and data gating options available. Options
include gating received data on preamble, or SWD detection.
Refer to Table 33 for further details.
Rev. 0 | Page 63 of 108
ADF7242
RC_PHY_RDY
RC_TX
REGISTER gp_cfg,
FIELD gpio_config
PREAMBLE SYNC
tx_mac_delay
PACKET
TRCLK_CKO_GP3
DT_GP1
1, (4)
IRQ2_TRFS_GP2
Figure 97. SPORT Operation in GFSK/FSK TX State
RC_RX
RC_PHY_RDY
PACKET
REGISTER gp_cfg,
FIELD gpio_config
NOISE PREAMBLE SYNC
rx_mac_delay
NOISE
TRCLK_CKO_GP3
DR_GP0
1, (4)
2, (5)
IRQ2_TRFS_GP2
TRCLK_CKO_GP3
DR_GP0
IRQ2_TRFS_GP2
TRCLK_CKO_GP3
DR_GP0
3, (6)
IRQ2_TRFS_GP2
Figure 98. Overview of SPORT Modes in GFSK/FSK RX State
Table 33. GFSK/FSK Mode SPORT Interface Configurations
Register gp_cfg,
Bit gpio_config
IRQ2_TRFS_GP2
DR_GP0
DT_GP1
TRCLK_CKO_GP3
1
RX: not used, low
TX: not used, low
RX: data output, changes at
falling edge of data clock
TX: not used
RX: not used
TX: data input, sampled at
rising edge of data clock
RX: data clock
TX: data clock
2
3
4
5
6
RX: goes high when sync RX: data output, changes at
RX: not used
RX: data clock, gated with
detection of preamble
match has been
detected
falling edge of data clock
RX: goes high when sync RX: data output, changes at
RX: not used
RX: data clock, gated with
detection of sync word
match has been
detected
falling edge of data clock
RX: not used, low
TX: not used, low
RX: data output, changes at
rising edge of data clock
TX: not used
RX: not used
TX: data input, sampled at
falling edge of data clock
RX: not used
RX: not used
RX: data clock
TX: data clock
RX: goes high when sync RX: data output, changes at
RX: data clock, gated with
detection of preamble
match has been
detected
rising edge of data clock
RX: goes high when sync RX: data output, changes at
RX: data clock, gated with
detection of sync word
match has been
detected
rising edge of data clock
Rev. 0 | Page 64 of 108
ADF7242
IEEE 802.15.4-2006 SPORT MODE
IEEE 802.15.4-2006 SPORT Mode Receive Operation
timing synchronization between incoming packets and the
network is required, and the SFD interrupt (rx_sfd) cannot be
used to achieve this. When in IEEE 802.15.4-2006 packet mode
(Register rc_cfg, Field rc_mode = 0), set Register gp_cfg, Field
gpio_config = 7 (0x32C[7:0]) to enable the symbol clock output.
The ADF7242 provides an IEEE 802.15.4-2006 operating mode
in which the SPORT interface is active and the packet manager
is bypassed. It allows the reception of packets of arbitrary
length. The mode is enabled by setting Register rc_cfg,
Field rc_mode = 2 (0x13E[7:0]) and Register gp_cfg, Field gpio_
config = 1 (0x32C[7:0]). When the SFD is detected, data and
clock signals appear on the SPORT outputs, DR_GP0 and
TRCLK_CKO_GP3, respectively. The SPORT interface remains
active until an RC_RX command is reissued or the RX state is
exited by another command. The rx_pkt_rvcd interrupt is not
available in this mode. Figure 7 illustrates the timing for this
configuration. Refer to Table 34 for details of pins relevant to
the SPORT interface in IEEE 802.15.4-2006 mode.
IEEE 802.15.4-2006 SPORT Mode Transmit Operation
IEEE 802.15.4-2006 TX SPORT mode is enabled by setting
Register rc_cfg, Field rc_mode = 3. It is necessary for the host
MCU to perform the IEEE 802.15.4 chipping sequence in
this mode. The data, sent through the SPORT interface on
Pin DT_GP1, should be synchronized with the clock signal
that appears on Pin TRCLK_CKO_GP3. Figure 9 shows the
timing for this configuration. As in GFSK/FSK TX SPORT
mode, the polarity of this clock signal can be set by Register
gp_cfg, Field gpio_config. The tx_pkt_sent interrupt is not
available in this mode. See Table 34 for details of pins relevant
to this SPORT mode.
Receive Symbol Clock in IEEE 802.15.4-2006 SPORT
Mode
The ADF7242 offers a symbol clock output option during IEEE
802.15.4 packet reception. This option is useful when a tight
Table 34. IEEE 802.15.4 Mode SPORT Interface Configuration
Register
gp_cfg, Field
gpio_config
Register
rc_cfg, Field
rc_mode
IRQ2_TRFS_GP2
DR_GP0
DT_GP1
RXEN_GP5
RXEN_GP6
TRCLK_CKO_GP3
3
2
RX: ignore
RX: data output,
changes at rising
edge of data
clock
RX: ignore
RX: ignore
RX: ignore
RX: data clock
7
1
2
3
RX: ignore
TX: ignore
RX: Symbol 0
TX: ignore
RX: Symbol 1
RX: Symbol 2 RX: Symbol 3
RX: symbol clock
TX: data clock
TX: data input, TX: ignore
sampled at
TX: ignore
rising edge of
data clock
4
3
TX: ignore
TX: ignore
TX: data input, TX: ignore
sampled at
TX: ignore
TX: data clock
falling edge of
data clock
Rev. 0 | Page 65 of 108
ADF7242
DEVICE CONFIGURATION
Table 36 through to Table 42 detail the values that should be
written to the register locations given in Table 35 to configure
the ADF7242 in the desired mode of operation.
After a cold start, or wake-up from sleep, it is necessary to
configure the ADF7242. The device can be configured in four
primary ways: an IEEE 802.15.4-2006 packet mode, an IEEE
802.15.4-2006 SPORT mode, and GFSK/FSK packet and
GFSK/FSK SPORT modes. Registers applicable to the set-up
each of the four primary modes are detailed in Table 35.
If it is desired to transition from a GFSK/FSK mode to an
IEEE.802.15.4-2006 mode, or vice-versa, it is necessary to first
issue the RC_RESET command.
Table 35. Register Writes Required to Configure the ADF7242
IEEE 802.15.4
Packet Mode
IEEE 802.15.4
SPORT Mode
FSK Packet
Mode
FSK SPORT
Mode
Register Group Description
RFIO Port
Register(s)
0x39B
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Packet/SPORT Mode Selection
SPORT Mode Configuration
Sync Word
0x13E
0x32C
Yes
Yes1
0x10C, 0x10D, 0x10E,
0x3F41
Yes1
Yes
Sync Word Configuration
Number of Preamble Bytes to
Transmit
Number of Preamble Validation
Bytes
0x10F
0x102
Yes
Yes
Yes
0x3F32
Yes
Data Rate
0x30E, 0x30F
0x304
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Frequency Deviation
Discriminator BW
Postdemodulation BW
Digital Filter Settings
Transmit Filters
Analog Filter BW
Synthesizer Lock Time
AGC
0x305
0x38B
0x389
0x306
Yes
0x39B
0x335
0x3B4, 0x3B6, 0x3B7,
0x3B8, 0x3BA, 0x3BC
AGC Lock
OCL
0x3B2
Yes
Yes
Yes
Yes
0x3BF, 0x3C4, 0x3D2,
0x3D3,0x3D4, 0x3D5,
0x3D6, 0x3D7, 0x3E0
AFC
AFC Lock
0x3F8, 0x3F9
0x3F7
Yes
Yes
Yes
Yes
1 These apply only when the user wishes to program a nonstandard SFD.
2 This register should only be written to in GFSK/FSK packet mode because the default setting of 0x05 is used in IEEE 802.15.4 packet mode.
Rev. 0 | Page 66 of 108
ADF7242
Table 37. Settings Common to All GFSK/FSK Configurations
CONFIGURATION VALUES COMMON TO IEEE
802.15.4 AND GFSK/FSK MODES
Address
0x335
0x3B2
0x3B4
0x3B6
0x3B7
0x3B8
0x3BA
0x3BC
0x3BF
0x3C4
0x3D2
0x3D3
0x3D4
0x3D5
0x3D6
0x3D7
0x3E0
0x3F3
Register Name
Value
0x28
0x34
0x80
0x37
0x2A
0x1D
0x24
0x7B
0x00
0x07
0x1A
0x19
0x1E
0x1E
0x1E
0x00
0xF0
0x01
synt
If it is desired to use RF Port 1 rather than RF Port 2 (see the RF
Port Configurations/Antenna Diversity section), the value
specific to the desired operating mode given in Table 36 should
be written to the relevant register field.
agc_cfg1
agc_max
agc_cfg2
agc_cfg3
agc_cfg4
agc_cfg6
agc_cfg7
ocl_cfg0
ocl_cfg1
ocl_bw0
ocl_bw1
ocl_bw2
ocl_bw3
ocl_bw4
ocl_bws
ocl_bw13
preamble_num_validate
Table 36. Settings Required to Select Between LNA Port 1
and LNA Port 2
Address
Register Field
Value
0x39B [6:4]
rxfe_cfg,
lna_sel
0x0: LNA1
0x1: LNA2
CONFIGURATION VALUES FOR GFSK/FSK PACKET
AND SPORT MODES
If it is desired to use either GFSK/FSK packet or SPORT mode,
the host MCU should write the configuration values shown in
Table 37 to the given register locations. These are common to all
GFSK/FSK packet and SPORT modes. Depending on the
desired data rate, the relevant values from Table 38 should also
be written.
Table 38. Data Rate-Specific GFSK/FSK Settings
Register or
Field Name
50 kbps
FSK
62.5 kbps 100 kbps
125 kbps
FSK
250 kbps
GFSK
500 kbps
GFSK
1 Mbps
GFSK
2 Mbps
GFSK
Address
FSK
FSK
0x1021
fsk_preamble
0x04
(6 bytes)
0x03
0x37
0x00
0x01
0xF4
0x17
0x08
0x6
0x04
(6 bytes)
0x06
0x37
0x00
0x02
0x71
0x17
0x08
0x6
0x05
(7 bytes)
0x03
0x6B
0x00
0x03
0xE8
0x17
0x0D
0x6
0x05
(7 bytes)
0x06
0x37
0x00
0x04
0xE2
0x17
0x11
0x6
0x05
(7 bytes)
0x0D
0x19
0x02
0x09
0xC4
0x12
0x20
0x6
0x05
(7 bytes)
0x19
0x0D
0x03
0x13
0x88
0x0A
0x3D
0x6
0x07
(9 bytes)
0x19
0x0D
0x03
0x27
0x10
0x05
0x6E
0x6
0x09
(11 bytes)
0x32
0x06
0x03
0x4E
0x20
0x05
0xAA
0xD
0x304
0x305
0x306
0x30E
0x30F
0x389
0x38B
tx_fd
dm_cfg0
tx_m
dr0
dr1
Iirf_cfg
dm_cfg1
0x39B [3:0] rxfe_cfg,
rxbb_bw_ana
1 This register should be written to in GFSK/FSK packet mode only. The preamble length transmitted that is given in this table is correct for the values of Register
preamble_num_validate given in Table 37 and Register sync_config given in Table 40, where sync_word0 is padded with one byte of preamble. Refer to the
Transmitter in GFSK/FSK Mode section for details.
Rev. 0 | Page 67 of 108
ADF7242
To select between packet mode and SPORT mode for
GFSK/FSK, write the values given in Table 39.
To enable the AFC, write the values given in Table 41.
Table 41. AFC Configuration Settings for GFSK/FSK
Address Register Name Value Comment
Table 39. Settings for GFSK/FSK Packet and SPORT Modes
Address Register Name Packet Mode SPORT Mode
0x3F7
0x3F8
0x3F9
afc_cfg
0x07
0x99
0x50
By default, AFC is locked
on preamble detection.
Default AFC ki and kp
values.
The AFC pull-in range is
programmable. Here it is
set to 80 kHz.
0x13E
0x32C
rc_cfg
0x04
N/A
0x03
afc_ki_kp
afc_range
gp_cfg
Refer to Table 33
Table 40 gives recommended sync word configuration values.
In this example, the sync word length is set to 16 bits so that the
sync word will be 0x7F31. Any bits in the sync_word0, sync_
word1, or sync_word2 register that are excluded by the setting
in sync_len must be filled with preamble pattern. Refer to the
Receiver in GFSK/FSK Mode section of the datasheet for details.
CONFIGURATION VALUES FOR IEEE 802.15.4-
2006 PACKET AND SPORT MODES
No register writes are required to configure IEEE 802.15.4
packet mode unless it is desired to select RF Port 1 rather than
RF Port 2. For SPORT mode, the values detailed in Table 42
should be written to the ADF7242.
Table 40. Example Sync Word Configuration for GFSK/FSK
Register or
Field Name
Address
Value Comment
0x10C
sync_word0 0x31
sync_word1 0x7F
sync_word2 0xAA
Sync word is fully
programmable.
Sync word is fully
programmable.
Sync word is fully
programmable.
A sync word tolerance of 0
errors is recommended.
This should match the
desired sync word set in
Register 0x10C to Register
0x10E.
Table 42. IEEE 802.15.4 Configuration Settings
Address
0x13E
0x306
Register Name
rc_cfg
tx_m
Packet Mode
SPORT Mode
See Table 34
0x01
0x10D
0x10E
N/A
N/A
N/A
0x32C
gp_cfg
See Table 34
0x10F[6:5] sync_config, 0x0
sync_tol
0x10F [4:0] sync_config, 0x10
sync_len
Note that, if it is desired to use a nonstandard SFD, an
additional register write is required. Refer to the IEEE 802.15.4-
2006 Programmable SFD section for details.
Rev. 0 | Page 68 of 108
ADF7242
RF PORT CONFIGURATIONS/ANTENNA DIVERSITY
ADF7242 is equipped with two fully differential RF ports. Port 1
is capable of receiving, whereas Port 2 is capable of receiving or
transmitting. RF Port 1 comprises Pin RFIO1P and Pin RFIO1N,
and RF Port 2 comprises Pin RFIO2P and Pin RFIO2N. Only
one of the two RF ports can be active at any one time.
advisable to synchronize the antenna selection phase with the
preamble component of the packet. In a static communication
system, it is often sufficient to select the optimum antenna once.
Configuration C
Configuration C shows that connecting an external PA and/or
LNA is possible with a single external receive/transmit switch. The
PA transmits on RF Port 2. RF Port 1 is configured as the receive
input (Register rxfe_cfg, Field lna_sel = 0).
The availability of two RF ports facilitates the use of switched
antenna diversity and results in a simplified application circuit
if the ADF7242 is connected to an external LNA and/or PA.
Port selection for receive operation is configured through
Register rxfe_cfg, Field lna_sel (0x39B[6:4]).
ADF7242 provides two signals, RXEN_GP6 and TXEN_GP5, to
automatically enable an external LNA and/or a PA. If Register
ext_ctrl, Bit txen_en = 1, the ADF7242 outputs a logic high level
at the TXEN_GP5 pin while in TX state, and a logic low level
while in any other state. If Register ext_ctrl, Bit rxen_en = 1, the
ADF7242 outputs a logic high level at the RXEN_GP6 pin while
in RX state and a logic low level while in any other state.
Configuration A
Configuration A of Figure 99, is the default connection, where a
single antenna is connected to RF Port 2. This selection is made
by setting Register rxfe_cfg, Field lna_sel = 1 (default setting).
Configuration B
The RXEN_GP6 and TXEN_GP5 outputs have high impedance
in the sleep state. Therefore, appropriate pull-down resistors
must be provided to define the correct state of these signals
during power-down. See the PA Ramping Controller section for
further details on the use of an external PA, including details of
the integrated biasing block, which simplifies connection to PA
circuits based upon a single FET.
Configuration B shows a dual-antenna configuration that is
suitable for switched antenna diversity. In this case, the link
margin can be maximized by comparing the RSSI level of the
signal received on each antenna and thus selecting the optimum
antenna. In addition, for IEEE 802.15.4-2006 mode the SQI
value in Register lrb, Field sqi_readback can be used in the
antenna selection decision.
Configuration D
Suitable algorithms for the selection of the optimum antenna
depend on the particulars of the underlying communication
system. Switching between two antennas is likely to cause a
short interruption of the received data stream. Therefore, it is
Configuration D is similar to Configuration A, except that a
dipole antenna is used. In this case, a balun is not required.
RFIO1P
4
4
RFIO1P
LNA
LNA
BALUN
BALUN
RFIO1N
5
5
RFIO1N
PA
PA
RFIO2P
RFIO2N
RFIO2P
RFIO2N
6
7
6
7
LNA
LNA
BALUN
A
B
RXEN_GP6
RFIO1P
26
4
4
5
RFIO1P
RFIO1N
LNA
LNA
LNA
PA
BALUN
RFIO1N
5
PA
LNA
PA
LNA
RFIO2P
RFIO2N
RFIO2P
RFIO2N
6
7
6
7
MATCH
NETWORK
BALUN
TXEN_GP5
25
D
C
Figure 99. RF Interface Configuration Options (A: Single Antenna; B: Antenna Diversity; C: External LNA/PA; D: Dipole Antenna)
Rev. 0 | Page 69 of 108
ADF7242
AUXILLARY FUNCTIONS
TEMPERTURE SENSOR
WAKE-UP CONTROLLER (WUC)
Circuit Description
To perform a temperature measurement, the MEAS state is
invoked using the RC_MEAS command. The result can be read
back from Register adc_rbk, Field adc_out (0x3AE[5:0]). Averag-
ing multiple readings improves the accuracy of the result. The
temperature sensor has an operating range from −40°C to +85°C.
The ADF7242 features a 16-bit wake-up timer with a programma-
ble prescaler. The 32.768 kHz RC oscillator or the 32.768 kHz
external crystal provides the clock source for the timer. This tick
rate clocks a 3-bit programmable prescaler whose output clocks
a preloadable 16-bit down counter. An overview of the timer
circuit is shown in Figure 100 lists the possible division rates for
the prescaler. This combination of programmable prescaler and
16-bit down counter gives a total WUC range of 30.52 μs to
36.4 hours.
The die (ambient) temperature is calculated as follows:
t
die = (4.72°C × Register adc_rbk, Field adc_out) + 65.58°C
+ correction value.
where correction value can be determined by performing a
readback at a single known temperature. Note also that averag-
ing a number of ADC readbacks can improve the accuracy of the
temperature measurement.
Table 43. Prescaler Division Factors
Tick
timer_prescal (0x316[2:0]) 32.768 kHz Divider Period
BATTERY MONITOR
000
001
010
011
100
101
110
111
1
4
8
16
128
1024
81,92
65,536
30.52 μs
122.1 μs
244.1 μs
488.3 μs
3.91 ms
31.25 ms
250 ms
The battery monitor features very low power consumption and
can be used in any state other than the sleep state. The battery
monitor generates a batt_alert interrupt for the host MCU
when the battery voltage drops below the programmed
threshold voltage. The default threshold voltage is 1.7 V, and
can be increased in 62 mV steps to 3.6 V with Register bm_cfg,
Field battmon_voltage (0x3E6[4:0]).
2000 ms
An interrupt generated when the wake-up timer has timed out
can be enabled in Register irq1_en0 or Register irq2_en0.
HARDWARE TIMER
tmr_cfg1[6:3]
(ADDRESS 0x317)
tmr_cfg0[2:0]
(ADDRESS 0x316)
tmr_rld0[15:8], tmr_rld1[7:0]
(ADDRESS 0x318, 0x319)
32.768kHz
RC
OSCILLATOR
WAKE UP
irq_src0[2]
(ADDRESS 0x3CB)
16-BIT DOWN
COUNTER
PRESCALER
32.768kHz
TICK RATE
32.768kHz
XTAL
Figure 100. Hardware Wake-Up Timer Diagram
Rev. 0 | Page 70 of 108
ADF7242
WUC Configuration and Operation
The calibration time is typically 1 ms. When the calibration is
complete Register wuc_32khzosc_status, Field rc_osc_cal_ready
is high. Following calibration, the host MCU can transition to
the SLEEP_BBRAM_RCO sleep state, by following the full
procedure given in the WUC Configuration and Operation
section.
The wake-up timer can be configured as follows:
•
The clock signal for the timer is taken from the external
32.768 kHz crystal or the internal RC oscillator. This is
selectable via Register tmr_cfg1, Bit sleep_config
(0x317[6:3]).
TRANSMIT TEST MODES
•
A 3-bit prescaler, which is programmable via Register
tmr_cfg0, Bit timer_prescal (0x316[2:0]) determines the
tick period.
The ADF7242 has various transmit test modes that can be used
in IEEE 802.15.4-2006 and GFSK/FSK SPORT modes. These
test modes can be enabled by writing to Register tx_fsk_test
(Location 0x3F0), as described in Table 44. A continuous packet
transmission mode is also available in IEEE 802.15.4-2006 and
GFSK/FSK packet modes. This mode can be enabled using the
following procedure:
This is followed by a preloadable 16-bit down counter. After the
clock is selected, the reload value for the down counter
(tmr_rld0 and tmr_rld1) and the prescaler values (Register
tmr_cfg0, Bit timer_prescal) can be programmed. When the
clock has been enabled, the counter starts to count down at the
tick rate starting from the reload value. If wake-up interrupts
are enabled, the timer unit generates an interrupt when the
timer value reaches 0x0000. When armed, the wake-up
interrupt triggers a wake-up from sleep.
1. An IEEE 80.215.4-2006 or a GFSK/FSK packet with
random payload should be written to TX_BUFFER as
described in the Transmitter section. It is recommended to
use a packet with the maximum length of 127 bytes.
2. Set Register buffercfg, Field trx_mac_delay = 1.
3. Set Register buffercfg, Field tx_buffer_mode = 3.
4. Set Register pkt_cfg, Field skip_synth_settle = 1.
5. Issue Command RC_TX. The transmitter continuously
transmits the packet stored in TX_BUFFER.
The reliable generation of wake-up interrupts requires the
WUC timeout flag to be reset immediately after the reload value
has been programmed. To do this, first write 1and then write 0
to Register tmr_ctrl, Field wake_timer_flag_reset. To enable
automatic wake-up from the sleep state, arm the timer unit for
wake-up operation by writing 1 to Register tmr_cfg1, Field
wake_on_timeout. After writing this sequence to the ADF7242,
a sleep command can be issued.
6. If Command RC_PHY_RDY is issued at any point after
this step, all the preceding configuration registers must be
rewritten to the device before reissuing Command RC_TX.
Note that the transmitter momentarily transmits an RF carrier
between packets due to a finite delay from when the packet
handler finishes transmitting a packet in TX_BUFFER and
going back to transmit the start of TX_BUFFER again.
Calibrating the RC oscillator
The RC oscillator is not automatically calibrated. If it is desired
to use the RC oscillator as the clock source for the WUC, the
host MCU should initiate a calibration. This can be performed
at any time in advance of entering the sleep state. To perform a
calibration, the host MCU should
•
•
Set Register tmr_ctrl, Field wuc_rc_osc_cal = 0
Set Register tmr_ctrl, Field wuc_rc_osc_cal = 1
Table 44. 0x3F0: tx_fsk_test
Bit
[7:4]
3
2
1
Name
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value Description
Reserved
zero_only
one_only
carrier_only
Reserved
2
0
0
0
0
Reserved, set to default.
Transmit 0 only (fCH − fDEV) in GFSK/FSK sport mode.
Transmit 1 only (fCH + fDEV) in GFSK/FSK sport mode.
Transmits unmodulated tone at the programmed frequency fCH.
Reserved, set to default.
0
Rev. 0 | Page 71 of 108
ADF7242
SERIAL PERIPHERAL INTERFACE (SPI)
GENERAL CHARACTERISTICS
The ADF7242 is equipped with a 4-wire SPI interface, using the
CS
All commands are executed after
goes high again or at the
next positive edge of the SCLK input. The latter condition
occurs in the case of a memory access command. In this case,
the command is executed on the positive SCLK clock edge
corresponding to the most significant bit of the first parameter
input must be brought high again after a
command has been shifted into the ADF7242 to enable the
recognition of successive command words. This is because a
CS
SCLK, MISO, MOSI, and
pins. The ADF7242 always acts as
a slave to the host MCU. Figure 101 shows an example connec-
tion diagram between the host MCU and the ADF7242. The
diagram also shows the direction of the signal flow for each pin.
The SPI interface is active and the MISO output enabled only
CS
word. The
CS
while the
input is low. The interface uses a word length of
CS
single command can be issued only during a
(with the exception of a double NOP command).
low period
eight bits, which is compatible with the SPI hardware of most
microprocessors. The data transfer through the SPI interface
occurs with the most significant bit of address and data first.
Refer to Figure 3 for the SPI interface timing diagram. The
MOSI input is sampled at the rising edge of SCLK. As
CS
RC OR SPI
COMMAND
MOSI
commands or data are shifted in from the MOSI input at the
SCLK rising edge, the status word or data is shifted out at the
STATUS
MISO
CS
MISO pin synchronous with the SCLK clock falling edge. If
is brought low, the most significant bit of the status word
appears on the MISO output without the need for a rising clock
edge on the SCLK input.
Figure 102. Command Write
The execution of certain commands by the radio controller may
take several instruction cycles, during which the radio control-
ler unit is busy. Prior to issuing a radio controller command, it
is, therefore, necessary to read the status word to determine if
the ADF7242 is ready to accept a new radio controller command.
This is best accomplished by shifting in SPI_NOP commands,
which cause status words to be shifted out. The RC_READY
variable is used to indicate when the radio controller is ready to
accept a new RC command, whereas the SPI_READY variable
indicates when the memory can be accessed. To take the burden
of repeatedly polling the status word off the host MCU for
complex commands such as RC_RX, RX_TX, and RC_PHY_RDY,
the IRQ handler can be configured to generate an RC_READY
interrupt. See the Interrupt Controller section for details.
Otherwise, the user can program timeout periods according to
the command execution times provided under the state transi-
tion timing given in Table 10 and Table 11.
VBAT
CS
SCLK
MOSI
MISO
PF1
ADF7242
SCLK
MOSI
MISO
GPI
ADSP-21xx
OR
IRQ1_GP4
BLACKFIN
DSP
IRQ2_TRFS_GP2
DR_GP0
RFS
DR
DT
DT_GP1
RSCLK
TSCLK
TRCLK_CKO_GP3
Figure 101. SPI Interface Connection
COMMAND ACCESS
The ADF7242 is controlled through commands. Command
words are single-byte instructions that control the state
transitions of the radio controller and access to the registers and
packet RAM. The complete list of valid commands is given in
Table 45. Commands with the RC prefix are handled by the
radio controller, whereas memory access commands, which
have the SPI prefix are handled by an independent controller.
Thus, SPI commands can be issued independent of the state of
the radio controller.
STATUS WORD
The status word of the ADF7242 is automatically returned over
the MISO each time a byte is transferred over the MOSI. The
meaning of the various status word bit fields is illustrated in
Table 46. The RC_STATUS field reflects the current state of the
radio controller. By definition, RC_STATUS reflects the state of
a completed state transition. During the state transition,
RC_STATUS maintains the value of the state from which the
state transition was invoked.
CS
A command is initiated by bringing
low and shifting in the
command word over the SPI as shown in Figure 102.
Rev. 0 | Page 72 of 108
ADF7242
Table 45. Command List
Command
Code
0xFF
0x10
Description
SPI_NOP
SPI_PKT_WR
No operation. Use for dummy writes.
Write data to the packet RAM starting from the transmit packet base address pointer,
Register txpb, Field tx_pkt_base (0x314[7:0]).
SPI_PKT_RD
0x30
Read data from the packet RAM starting from the receive packet base address pointer,
Register rxpb, Field rx_pkt_base (0x315[7:0]).
SPI_MEM_WR
SPI_MEM_RD
0x18 + memory address[10:8] Write data to MCR or packet RAM sequentially.
0x38 + memory address[10:8] Read data from MCR or packet RAM sequentially.
SPI_MEMR_WR 0x08 + memory address[10:8] Write data to MCR or packet RAM as a random block.
SPI_MEMR_RD 0x28 + memory address[10:8] Read data from MCR or packet RAM as a random block.
SPI_PRAM_WR 0x1E
Write data to the program RAM.
RC_SLEEP
RC_IDLE
RC_PHY_RDY
RC_RX
RC_TX
RC_MEAS
RC_CCA
0xB1
0xB2
0xB3
0xB4
0xB5
0xB6
0xB7
0xC7
Invoke transition of the radio controller into the sleep state
Invoke transition of the radio controller into the idle state
Invoke transition of the radio controller into the PHY_RDY state
Invoke transition of the radio controller into the RX state
Invoke transition of the radio controller into the TX state
Invoke transition of the radio controller into the MEAS state
Invoke clear channel assessment
RC_PC_RESET
Program counter reset. This should only be used after a firmware download to the
program RAM
RC_RESET
0xC8
Resets the ADF7242 and puts it in the sleep state
Table 46. SPI Status Word
Bit
Name
Description
7
SPI_READY
0: SPI is not ready for access.
1: SPI is ready for access.
6
IRQ_STATUS
0: no pending interrupt condition.
1: pending interrupt condition. (IRQ_STATUS = 1 when either the IRQ1_GP4 or
IRQ2_TRFS_GP2 pin is high)
5
4
RC_READY
0: radio controller is not ready to accept RC_xx command strobe.
1: radio controller is ready to accept new RC_xx command strobe.
0: channel busy.
CCA_RESULT
1: channel idle.
Valid when Register irq_src1, Bit cca_complete (0x3CC[0]) is asserted.
[3:0]
RC_STATUS
Radio controller status:
0: reserved.
1: idle.
2: MEAS.
3: PHY_RDY.
4: RX.
5: TX.
6 to 15: reserved.
Rev. 0 | Page 73 of 108
ADF7242
MEMORY MAP
The various memory locations used by the ADF7242 are shown
in Figure 103. The radio control and packet management of the
part are realized through the use of an 8-bit, custom processor
and an embedded ROM. The processor executes instructions
stored in the embedded program ROM. There is also a local
RAM, subdivided into three sections, that is used as a data
packet buffer, both for transmitted and received data (packet
RAM), and for storing the radio and packet management
configuration (BBRAM and MCR). The RAM addresses of
these variables are 11 bits in length.
PROGRAM RAM
The program RAM consists of 2 kB of volatile memory. This
memory space is used for various software modules, such as
address filtering and CSMA/CA, which are available from
Analog Devices. The software modules are downloaded to the
program RAM memory space over the SPI by the host
microprocessor. See the Program RAM Write subsection of the
Memory Access section for details on how to write to the
program RAM.
PACKET RAM
BBRAM
The packet RAM consists of 256 bytes of memory space from
Address 0x000 to Address 0x0FF, as shown in Figure 103. This
memory is allocated for storage of data from valid received
packets and packet data to be transmitted. The packet manager
stores received payload data at the memory location indicated
by the value of Register rxpb, Field rx_pkt_base, the receive
address pointer. The value of Register txpb, Field tx_pkt_base,
the transmit address pointer, determines the start address of
data to be transmitted by the packet manager. This memory can
be arbitrarily assigned to store single or multiple transmit or
receive packets, both with and without overlap as shown in
Figure 104. The rx_pkt_base value should be chosen to ensure
that there is enough allocated packet RAM space for the
maximum receiver payload length.
The 64-byte battery back-up, or BBRAM, is used to maintain
settings needed at wake-up from sleep state by the wake-up
controller.
MODEM CONFIGURATION RAM (MCR)
The 256-byte modem configuration RAM, or MCR, contains
the various registers used for direct control or observation of
the physical layer radio blocks of the ADF7242. Contents of the
MCR are not retained in the sleep state.
PROGRAM ROM
The program ROM consists of 4 kB of nonvolatile memory. It
contains the firmware code for radio control, packet manage-
ment, and smart wake mode.
11-BIT
ADDRESSES
0x3FF
PROGRAM
MCR
REGISTER prampg, FIELD pram_page[3:0]
RAM
256 BYTES
2kB
ADDRESS
[7:0]
0x300
CS
MISO
NOT USED
PROGRAM
ROM
SPI
MOSI
0x13F
4kB
SCLK
BBRAM
64 BYTES
SPI/PH
0x100
MEMORY
ARBITRATION
0x0FF
PACKET
MANAGER
PACKET
INSTRUCTION/DATA
[7:0]
PACKET
RAM
MANAGER
256 BYTES
ADDRESS/
DATA
MUX
CLOCK
8-BIT
PROCESSOR
ADDRESS[10:0]
DATA[7:0]
0x000
Figure 103. ADF7242 Memory Map
Rev. 0 | Page 74 of 108
ADF7242
TRANSMIT
AND RECEIVE
PACKET
256-BYTE TRANSMIT
OR RECEIVE
PACKET
MULTIPLE TRANSMIT
AND RECEIVE
PACKETS
tx_pkt_base
rx_pkt_base
tx_pkt_base
(PACKET 1)
tx_pkt_base
0x000
0x000
0x000
TRANSMIT
PAYLOAD
TRANSMIT
PAYLOAD
tx_pkt_base
(PACKET 2)
TRANSMIT
PAYLOAD 2
rx_pkt_base
(PACKET 1)
TRANSMIT OR
RECEIVE
RECEIVE
PAYLOAD
rx_pkt_base
PAYLOAD
RECEIVE
PAYLOAD
rx_pkt_base
(PACKET 2)
RECEIVE
PAYLOAD 2
0x0FF
0x0FF
0x0FF
Figure 104. Example Packet RAM Configurations Using the Transmit Packet and Receive Packet Address Pointers
Rev. 0 | Page 75 of 108
ADF7242
MEMORY ACCESS
Memory locations are accessed by invoking the relevant SPI
command. An 11-bit address is used to identify registers or
locations in the memory space. The most significant three bits
of the address are incorporated into the command by append-
ing them as the LSBs of the command word. Figure 105
illustrates the command, address, and data partitioning. The
various SPI memory access commands are different depending
on the memory location being accessed. This is described in
Table 47.
An SPI command should be issued only if the SPI_READY bit
of the status word is high.
In addition, an SPI command should not be issued while the
radio controller is initializing. SPI commands can be issued in
any radio controller state including during state transition.
CS
SPI_MEM_WR
MEMORY ADDRESS
BITS[7:0]
DATA BYTE
MOSI
5 BITS
MEMORY ADDRESS
BITS[10:0]
DATA
n × 8 BITS
Figure 105. SPI Memory Access Command/Address Format
Table 47. Summary of SPI memory access commands
SPI Command Command Value
Description
SPI_PKT_WR
SPI_PKT_RD
SPI_MEM_WR
= 0x10
Write telegram to the packet RAM starting from the transmit packet base address pointer,
Register txpb, Field tx_pkt_base (0x314[7:0]).
Read telegram from the packet RAM starting from receive packet base address pointer,
Register rxpb, Field rx_pkt_base (0x315[7:0]).
Write data to BBRAM, MCR, or packet RAM sequentially. An 11-bit address is used to identify
memory locations. The most significant three bits of the address are incorporated into the
command (xxxb). This command is followed by the remaining eight bits of the address.
= 0x30
= 0x18 (packet RAM)
= 0x19 (BBRAM)
= 0x1B (MCR)
SPI_MEM_RD
= 0x38 (packet RAM)
= 0x39 (BBRAM)
= 0x3B (MCR)
Read data from BBRAM, MCR, or packet RAM sequentially. An 11-bit address is used to identify
memory locations. The most significant three bits of the address are incorporated into the
command (xxxb). This command is followed by the remaining eight bits of the address, which
is subsequently followed by the appropriate number of SPI_NOP commands.
SPI_MEMR_WR = 0x08 (packet RAM)
= 0x09 (BBRAM)
Write data to BBRAM/MCR or packet RAM at random.
= 0x0B (MCR)
SPI_MEMR_RD = 0x28 (packet RAM)
= 0x29 (BBRAM)
Read data from BBRAM/MCR or packet RAM at random.
= 0x2B (MCR)
SPI_PRAM_WR =0x1E (program RAM)
Write data to program RAM.
Read data from program RAM
No operation. Use for dummy writes when polling the status word and used as dummy data on
the MOSI line when performing a memory read.
SPI_PRAM_RD
SPI_NOP
=0x3E (program RAM)
= 0xFF
Rev. 0 | Page 76 of 108
ADF7242
relative location of a byte to Address Pointer rx_pkt_base
(Register rxpb; 0x315[7:0]) or Address Pointer tx_pkt_base
(Register txpb; 0x314[7:0]), respectively.
WRITING TO THE ADF7242
Block Write
Packet RAM memory locations can be written to in block
format using the SPI_PKT_WR. The SPI_PKT_WR command
is 0x10. This command provides pointer-based write access to
the packet RAM. The address of the location written to is calcu-
lated from the base address in Register txpb, Field tx_pkt_base
(0x314[7:0]) plus an index. The index is zero for the first data
word following the command word, and is auto-incremented
for each consecutive data word written. The first data word follow-
ing an SPI_PKT_WR command is thus stored in the location
with Address txpb, Field tx_pkt_base (0x314[7:0]), the second
in packet RAM location with Address txpb, Field tx_pkt_base + 1,
and so on. This feature makes this command efficient for bulk
writes of data that recurrently begin at the same address. Figure 106
shows the access sequence for Command SPI_PKT_WR.
Program RAM Write
The program RAM can only be written to using the memory
block write, as illustrated in Figure 109. The SPI_PRAM_WR
command is 0x1E. The program RAM is organized in eight
pages with a length of 256 bytes each. The code module must be
stored in the program RAM starting from Address 0x0000, or
Address 0x00 in Page 0. The current program RAM page is
selected with Register prampg, Field pram_page (0x313[3:0]).
Prior to uploading the program RAM, the radio controller code
module must be divided into blocks of 256 bytes commensurate
with the size of the program RAM pages. Each 256-byte block is
uploaded into the currently selected program RAM page using
the SPI_PRAM_WR command. Figure 109 illustrates the
sequence required for uploading a code block of 256 bytes to a
PRAM page. The SPI_PRAM_WR command code is followed
by Address Byte 0x00 to align the code block with the base
address of the program RAM page. Figure 110 shows the overall
upload sequence. With the exception of the last page written to
the program RAM, all pages must be filled with 256 bytes of
module code.
The MCR, BBRAM, and packet RAM memory locations can be
written to in block format using the SPI_MEM_WR command.
The SPI_MEM_WR command code is 00011xxxb, where xxxb
represent Bits[10:8] of the first 11-bit address. If more than one
data byte is written, the write address is automatically incre-
CS
mented for every byte sent until is set high, which terminates
the memory access command. See Figure 107 for more details.
The maximum block write for the MCR, packet RAM, and
BBRAM memories are 256 bytes, 256 bytes, and 64 bytes,
respectively. These maximum block-write lengths should not be
exceeded.
READING FROM THE ADF7242
Block Read
Command SPI_PKT_RD provides pointer-based read access
from the packet RAM. The SPI_PKT_RD command is 0x30.
The address of the location to be read is calculated from the base
address in Register rxpb, Field rx_pkt_base plus an index. The
index is zero for the first readback word. It is auto-incremented
for each consecutive SPI_NOP command. The first data byte
following a SPI_PKT_RD command is invalid and should be
ignored. Figure 111 shows the access sequence for Command
SPI_PKT_RD.
Example
Write 0x00 to the rc_cfg register (Location 0x13E).
•
The first five bits of the SPI_MEM_WR command are
00011.
•
•
•
•
The 11-bit address of rc_cfg is 00100111110.
The first byte sent is 00011001 or 0x19.
The second byte sent is 00111110 or 0x3E.
The third byte sent is 0x00.
The SPI_MEM_RD command can be used to perform a block
read of MCR, BBRAM, and packet RAM memory locations.
The SPI_MEM_RD command code is 00111xxxb, where xxxb
represent Bits[10:8] of the first 11-bit address. This command is
followed by the remaining eight bits of the address to be read
and then two SPI_NOP commands (dummy byte). The first
byte available after writing the address should be ignored, with
the second byte constituting valid data. If more than one data
byte is to be read, the read address is automatically incremented
for subsequent SPI_NOP commands sent. See Figure 112 for
more details.
Thus, 0x193F00 is written to the part.
Random Address Write
MCR, BBRAM, and packet RAM memory locations can be
written to in random address format using the SPI_MEMR_WR
command. The SPI_MEMR_WR command code is 00001xxxb,
where xxxb represent Bits[10:8] of the 11-bit address. The lower
eight bits of the address should follow this command and then
the data byte to be written to the address. The lower eight bits of
the next address are entered followed by the data for that
address until all required addresses within that block are
written, as shown in Figure 108. Note that the SPI_MEMR_WR
command facilitates the modification of individual elements of
a packet in RX_BUFFER and TX_BUFFER without the need to
download and upload an entire packet.
Random Address Read
MCR, BBRAM, and Packet RAM memory locations can be read
from in a nonsequential manner using the SPI_MEMR_RD
command. The SPI_MEMR_RD command code is 00101xxxb,
where xxxb represent Bits[10:8] of the 11-bit address. This
command is followed by the remaining eight bits of the address
to be written and then two SPI_NOP commands (dummy byte).
The address location of a particular byte in RX_BUFFER and
TX_BUFFER in the packet RAM is determined by adding the
Rev. 0 | Page 77 of 108
ADF7242
The data byte from memory is available on the second SPI_NOP
command. For each subsequent read, an 8-bit address should be
followed by two SPI_NOP commands as shown in Figure 113.
Thus, 0x393EFFFF is written to the part.
The value shifted out on the MISO line while the fourth byte is
sent is the value stored in the rc_cfg register.
Example
This allows individual elements of a packet in RX_BUFFER and
TX_BUFFER to be read without the need to download the
entire packet.
Read the value stored in the rc_cfg register.
•
•
•
•
•
•
The first five bits of the SPI_MEM_RD command are 00111.
The 11-bit address of rc_cfg register is 00100111111.
The first byte sent is 00111001, or 0x39.
The second byte sent is 00111110, or 0x3E.
The third byte sent is 0xFF (SPI_NOP).
Program RAM Read
The SPI_PRAM_RD command is used to read from the
program RAM. This may be performed to verify that a
firmware module has been correctly written to the program
RAM. Like the SPI_PRAM_WR command, the host MCU must
select the program RAM page to read via Register prampg, Field
pram_page. Following this, the host MCU may use the
SPI_PRAM_RD command to block read the selected program
RAM page. The structure of this command is identical to the
SPI_MEM_RD command.
The fourth byte sent is 0xFF.
[Max N = (256 – tx_pkt_base)]
CS
DATA FOR ADDRESS
[tx_pkt_base]
DATA FOR ADDRESS
[tx_pkt_base + 1]
DATA FOR ADDRESS
[tx_pkt_base + 2]
DATA FOR ADDRESS
[tx_pkt_base + 3]
DATA FOR ADDRESS
[tx_pkt_base + N]
MOSI
MISO
SPI_PKT_WR
STATUS
STATUS
STATUS
STATUS
STATUS
STATUS
Figure 106. Packet RAM Write
(tx_pkt_base is the address base pointer value for TX, which is programmed in Register txbp, Bit tx_pkt_base.)
[Max N = (256 – INITIAL ADDRESS)]
CS
DATA FOR
[ADDRESS]
DATA FOR
DATA FOR
DATA FOR
SPI_MEM_WR
STATUS
ADDRESS
STATUS
MOSI
[ADDRESS + 1]
[ADDRESS + 2]
[ADDRESS + N]
STATUS
STATUS
STATUS
STATUS
MISO
Figure 107. Memory (Register or Packet RAM) Block Write
CS
SPI_MEMR_WR
STATUS
ADDRESS 1
STATUS
DATA 1
ADDRESS 2
STATUS
DATA 2
DATA N
STATUS
MOSI
STATUS
STATUS
MISO
Figure 108. Memory (Register or Packet RAM) Random Address Write
Rev. 0 | Page 78 of 108
ADF7242
CS
SPI_MEM_WR
+0x03
PAGE NUMBER
n
0x13
SPI_PRAM_WR
STATUS
0x00
CODE[0x00]
STATUS
CODE[0xFF]
STATUS
MOSI
MISO
STATUS
STATUS
STATUS
STATUS
SET PRAM PAGE NUMBER n
UPLOAD 256 BYTES OF CODE TO PRAM PAGE NUMBER n
Figure 109. Upload Sequence for a Program RAM Page
DOWNLOAD 256 BYTES BLOCK 0
TO PRAM PAGE 0
DOWNLOAD 256 BYTES BLOCK 0
SET PRAM PAGE 0
SET PRAM PAGE 1
SET PRAM PAGE 2
TO PRAM PAGE 1
Figure 110. Download Sequence for Code Module
Max N = (256 – tx_pkt_base)
SPI_NOP
CS
MOSI
SPI_PKT_RD
STATUS
SPI_NOP
STATUS
SPI_NOP
SPI_NOP
SPI_NOP
DATA FROM
ADDRESS
rx_pkt_base
DATA FROM
ADDRESS
rx_pkt_base + 1
DATA FROM
ADDRESS
rx_pkt_base + 2
DATA FROM
ADDRESS
rx_pkt_base + N
MISO
Figure 111. Packet RAM Read
(rx_pkt_base is the address base pointer value for RX, which is programmed in Register rxbp, Bit rx_pkt_base.)
[Max N = (256 – INITIAL ADDRESS)]
CS
MOSI
SPI_MEM_RD
STATUS
ADDRESS
STATUS
SPI_NOP
STATUS
SPI_NOP
SPI_NOP
SPI_NOP
DATA FROM
ADDRESS
DATA FROM
ADDRESS + 1
DATA FROM
ADDRESS + N
MISO
Figure 112. Memory (Register or Packet RAM) Block Read
CS
ADDRESS 2
ADDRESS N
SPI_NOP
MOSI
MISO
SPI_MEM_RD
ADDRESS 1
ADDRESS 3
SPI_NOP
ADDRESS 4
DATA FROM
ADDRESS N-2
DATA FROM
ADDRESS N-1
DATA FROM
ADDRESS 1
DATA FROM
ADDRESS 2
DATA FROM
ADDRESS N
STATUS
STATUS
STATUS
Figure 113. Memory (Register or Packet RAM) Random Address Read
Rev. 0 | Page 79 of 108
ADF7242
DOWNLOADABLE FIRMWARE MODULES
The program RAM of the ADF7242 can be used to store
firmware modules for the on-chip processor that provide extra
functionality. The executable code for these firmware modules
and details on their functionality are available from Analog
Devices. See the Writing to the ADF7242 section for details on
how to download these firmware modules to program RAM.
Rev. 0 | Page 80 of 108
ADF7242
INTERRUPT CONTROLLER
resources. For instance, an rx_sfd interrupt can be associated
with a timer-capture unit of the MCU, while all other interrupts
are handled by a normal interrupt handling routine. When
operating in SPORT mode, Pin IRQ2_TRFS_GP2 acts as a
frame synchronization signal and is disconnected from the
interrupt controller.
CONFIGURATION
The ADF7242 is equipped with an interrupt controller that is
capable of handling up to 16 independent interrupt events. The
interrupt events can be triggered either by hardware circuits or
the packet manager and are captured in Register irq_src0
(0x3CB) and Register irq_src1(0x3CC).
When in the sleep state, the IRQ1_GP4 and IRQ2_TRFS_GP2
pins have high impedance.
The interrupt signals are available on two interrupt pins, IRQ1_
GP4 and IRQ2_TRFS_GP2. Each of the 16 interrupt sources
can be individually enabled or disabled. The irq1_en0 (0x3C7)
and irq1_en1 (0x3C8) registers control the functionality of the
IRQ1_GP4 interrupt pin. The irq2_en0 (0x3C9) and irq2_en1
(0x3CA) registers control the functionality of the IRQ2_TRFS_
GP2 interrupt pin. Refer to Table 48 and Table 49 for details on
which bits in the relevant interrupt source and interrupt enable
registers correspond to the different interrupts.
When not in the sleep state, Pin IRQ1_GP4 and Pin IRQ2_
TRFS_GP2 are configured as push-pull outputs, using positive
logic polarity.
Following a power-on reset or wake-up from sleep, Register
irq1_en0, Field powerup and Register irq2_en0, Field powerup
are set, while all other bits in the irq1_en0, irq1_en1, irq2_en0,
and irq2_en1 registers are reset. Therefore, a power-up interrupt
signal is asserted on the IRQ1_GP4 and IRQ2_TRFS_GP2 pins
after a power-on-reset event or wake-up from the sleep state.
Provided the wake-up from sleep event is caused by the wake-
up timer, the power-up interrupt signal can be used to power
up the host MCU.
The IRQ_STATUS bit of the SPI status word, is asserted if an
interrupt is present on either IRQ1 or IRQ2. This is useful for
host MCUs that may not have interrupt pins available.
The irq_src1 and irq_src0 registers can be read back to establish
the source of an interrupt. An interrupt is cleared by writing 1
to the corresponding bit location in the appropriate interrupt
source register (irq_src1 or irq_src0). If 0 is written to a bit
location in the interrupt source registers, its state remains
unchanged. This scheme allows interrupts to be cleared
individually and facilitates hierarchical interrupt processing.
After the ADF7242 is powered up, the rc_ready, wake-up, and
power-on reset interrupts are also asserted in the irq_src0
register. However, these interrupts are not propagated to the
IRQ1_GP4 and IRQ2_TRFS_GP2 pins because the correspond-
ing mask bits are reset. The irq_src0 and irq_src1 registers
should be cleared during the initialization phase.
The availability of two interrupt outputs permits a flexible
allocation of interrupt source to two different MCU hardware
REGISTER irq_src1
REGISTER irq_src0
INTERRUPT
SOURCES
(16 INTERRUPT SOURCES
AVAILABLE)
15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
INTERRUPT
MASKS
(2 × 16 INDEPENDANT
INTERRUPT MASKS)
REGISTER irq2_en1
REGISTER irq2_en0
REGISTER irq1_en1
REGISTER irq1_en0
INTERRUPT OUTPUTS
(2 INTERRUPT PINS AND
INTERRUPT PENDING BIT
AVAILABLE ON THE
STATUS_WORD)
IRQ1_GP4
Status_word[6]
IRQ2_TRFS_GP2
Figure 114. Interrupt Controller
Rev. 0 | Page 81 of 108
ADF7242
Table 48. Bit Locations in the Interrupt Source Register
irq_src1, with Corresponding Interrupt Enables in irq1_en1,
irq2_en1
tx_sfd
This interrupt is asserted if the SFD or SWD is transmitted
when in IEEE 802.15.4-2006 or GFSK/FSK packet mode.
Bit Name
Notes
rx_sfd
7
6
5
4
3
2
1
0
Reserved
Don’t care; set mask to 0.
Don’t care; set mask to 0.
Don’t care; set mask to 0.
TX packet transmission complete.
Packet received in RX_BUFFER.
SFD/SWD has been transmitted.
SFD/SWD has been detected.
CCA_RESULT in status word is valid.
This interrupt is asserted if a SFD or SWD is detected while in
the RX state in either IEEE 802.15.4 or GFSK/FSK mode.
Reserved
Reserved
tx_pkt_sent
rx_pkt_rcvd
tx_sfd
cca_complete
The interrupt is asserted at the end of a CCA measurement
following a RC_RX or RC_CCA command. The interrupt
indicates that the CCA_RESULT flag in the status word is valid.
rx_sfd
cca_complete
batt_alert
The interrupt is asserted if the battery monitor signals a battery
alarm. This occurs when the battery voltage drops below the
programmed threshold value. The battery monitor must be
enabled and configured. See the Battery Monitor section for
further details.
Table 49. Bit Locations in the Interrupt Source Register
irq_src0, with Corresponding Interrupt Enables in irq1_en0,
irq2_en0
Bit Name
Notes
7
6
5
Reserved Don’t care; set mask to 0.
Reserved Don’t care; set mask to 0.
batt_alert Battery voltage has dropped below
programmed threshold value.
rc_ready
The interrupt is asserted if the radio controller is ready to accept
a new command. This condition is equivalent to the rising edge
of the RC_READY flag in the status word.
4
3
por
rc_ready
Power-on reset event.
Radio controller ready to accept new
command.
wakeup
2
1
0
wakeup
powerup
Timer has timed out.
Chip is ready for access.
The interrupt is asserted if the WUC timer has decremented to
zero. Prior to enabling this interrupt, the WUC timer unit must
be configured with the tmr_cfg0, tmr_cfg1, tmr_rld0, and
tmr_rld1 registers. A wake-up interrupt can be asserted while
the ADF7242 is active or has woken up from the sleep state
through a timeout event. See the Wake-Up Controller (WUC)
section or further details.
Reserved Don’t care; set mask to 0.
DESCRIPTION OF INTERRUPT SOURCES
tx_pkt_sent
This interrupt is asserted when in IEEE 802.15.4-2006 or
GFSK/FSK packet mode and the transmission of a packet in
TX_BUFFER is complete.
powerup
The interrupt is asserted if the ADF7242 is ready for SPI access
following a wake-up from the sleep state. This condition reflects
a rising edge of the flag SPI_READY in the status word. If the
rx_pkt_rcvd
This interrupt is asserted when in IEEE 802.15.4-2006 or
GFSK/FSK packet mode and a packet with a valid FCS or CRC
has been received and is available in RX_BUFFER.
CS
ADF7242 has been woken `up from the sleep state using the
input, this interrupt is useful to detect that the ADF7242 has
powered up without the need to poll the MISO output. Register
irq1_mask, Field powerup and Register irq2_mask, Field
powerup are automatically set on exit from the sleep state.
Therefore, this interrupt is generated when a transition from
CS
sleep is triggered by
being pulled low or by a timeout event.
Rev. 0 | Page 82 of 108
ADF7242
APPLICATIONS CIRCUITS
C15
C14
C39
C40
C41
C28
SENSOR
32kHz
SCS
MOSI
SCLK
MISO
VBAT
32 31 30 29 28 27 26 25
MICRO-
CONTROLLER
R10
24
C18
C17
C16
R12
GPIO0
1
C21
C22
CREGRF1
GPIO1
MOSI
SCLK
MISO
CS
GND
BALP
BALM
23
22
21
2
3
4
RBIAS
MOSI
UNBAL
GND
CREGRF2
RFIO1P
RFIO1N
RFIO2P
RFIO2N
CREGRF3
SCLK
MISO
10
20
19
18
17
5
6
7
8
ADF7242
IRQ1IN
IRQ2IN
IRQ1_GP4
TRCLK_CKO_GP3
IRQ2_TRFS_GP2
DT_GP1
C25
C26
C32
C27
12
9
10 11 12 13 14 15 16
26MHz
C34
C29
C30
C32
C35
C36
C37
Figure 115. Typical ADF7242 Application Circuit Using Antenna Diversity
Rev. 0 | Page 83 of 108
ADF7242
C15
C14
C39
C40
C41
C28
32kHz
VBAT
32 31 30 29 28 27 26 25
R10
C18
C17
C16
C4
L3
DSP
BFxxx
R12
24
1
C5
C7
CREGRF1
GPIO1
MOSI
SCLK
MISO
CS
23
22
21
2
3
4
RBIAS
MOSI
C6
L1
SPI
CREGRF2
RFIO1P
RFIO1N
RFIO2P
RFIO2N
CREGRF3
SCLK
MISO
L2
20
19
18
17
5
6
7
8
ADF7242
IRQ1IN
IRQ1_GP4
TRCLK_CKO_GP3
IRQ2_TRFS_GP2
DT_GP1
L4
C8
SPORT
C9
C27
L6
C11
L5
C10
9
10 11 12 13 14 15 16
26MHz
C34
C29
C30
C32
C35
C36
C37
Figure 116. Typical ADF7242 Application Circuit with DSP Using Antenna Diversity
Rev. 0 | Page 84 of 108
ADF7242
C41
C28
C15
C14
C39
C40
32kHz
R14
R15
VBAT
32 31 30 29 28 27 26 25
R10
C18
C17
C16
DSP
R12
BFxxx
24
1
C21
C22
CREGRF1
RBIAS
GPIO1
CS
GND BALP
ENABLE
LNA
23
22
21
2
3
4
MOSI
SCLK
MISO
MOSI
SCLK
UNBAL
SPI
CREGRF2
RFIO1P
10
GND BALM
MISO
20
19
18
17
5
6
7
8
ADF7242
IRQ1IN
RFIO1N
RFIO2P
IRQ1_GP4
TRCLK_CKO_GP3
IRQ2_TRFS_GP2
DT_GP1
SPORT
C25
C26
RFIO2N
CREGRF3
ENABLE
GND BALP
PA
UNBAL
C27
12
GND BALM
9
10 11 12 13 14 15 16
26MHz
C34
C29
C30
C32
C35
C36
C37
Figure 117. Typical ADF7242 Application Circuit with External LNA and External PA
Rev. 0 | Page 85 of 108
ADF7242
6
0 7 2 - 9 1 0 8
5 P G _ X T E N
P 6 G _ E X N R
0 P G _ D R
2 G I D G E C R
D R U A D G
2 6 C N S O X
1 G I D G C R E
B T 1 A 7 _ P G _
3 2 C K S P O X
2 B T A _ N K 2 3 C S X O
T A D V D _ B
P 6 2 C S X O
H T N S Y E G R C
U A G R D C V O
3 B T A _ P U S P A V
B T 4 A _ P A O A P B I
O
V C E G R C
E L D D P A
Figure 118. Typical ADF7242 Application Circuit with Discrete External PA
Rev. 0 | Page 86 of 108
ADF7242
REGISTER MAP
It is recommended that configuration registers be programmed in the idle state. Note that all registers that include fields that are denoted
as RC_CONTROLLED must be programmed in the idle state only.
Reset values are shown in decimal notation.
Table 50. Register Map Overview
Address
0x100
0x102
0x105
0x106
0x107
0x108
0x109
0x10A
0x10B
0x10C
0x10D
0x10E
0x10F
0x111
0x13E
0x300
0x301
0x302
0x304
0x305
0x306
0x30C
0x30D
0x30E
0x30F
0x313
0x314
0x315
0x316
0x317
0x318
0x319
0x31A
0x31B
0x31E
0x32C
0x32D
0x335
0x33D
0x353
0x354
0x355
0x36E
0x36F
0x371
0x380
Register Name
Access Mode
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
Description
ext_ctrl
fsk_preamble
cca1
cca2
buffercfg
pkt_cfg
delaycfg0
delaycfg1
delaycfg2
sync_word0
sync_word1
sync_word2
sync_config
fsk_preamble_config
rc_cfg
ch_freq0
ch_freq1
ch_freq2
tx_fd
dm_cfg0
tx_m
rrb
lrb
dr0
dr1
prampg
txpb
rxpb
External LNA/PA and internal PA control configuration bits
GFSK/FSK preamble length configuration
RSSI threshold for CCA
CCA mode configuration
RX and TX Buffer configuration
Firmware download module enable/FCS/CRC control
RC_RX command to SFD or SWD search delay
RC_TX command to TX state delay
MAC delay extension
Sync Word Bits[7:0] of [23:0]
Sync Word Bits[15:8] of [23:0]
Sync Word Bits[23:16] of [23:0]
Sync word configuration
GFSK/FSK preamble configuration
Packet/SPORT mode configuration
Channel frequency settings—low byte
Channel frequency settings—middle byte
Channel frequency settings—two MSBs
Transmit frequency deviation register
Receive discriminator bandwidth register
Gaussian and preemphasis filter configuration
RSSI readback register
Signal quality indicator quality readback register
Data rate [bps/100], Bits[15:8] of [15:0]
Data rate [bps/100], Bits[7:0] of [15:0]
PRAM page
Transmit packet storage base address
Receive packet storage base address
Wake-up timer configuration register—high byte
Wake-up timer configuration register—low byte
Wake-up timer value register—high byte
Wake-up timer value register—low byte
Wake-up timer timeout flag configuration register
32 kHz oscillator/WUC status
Battery monitor and external PA bias enable
GPIO configuration
GPIO configuration
Synthesizer lock time
RC calibration setting
Overwrite value for the VCO frequency band.
Overwrite value for the VCO bias current DAC.
VCO calibration settings overwrite enable
PA bias control
VCO calibration parameters
26 MHz crystal oscillator configuration
Readback VCO band after calibration
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
tmr_cfg0
tmr_cfg1
tmr_rld0
tmr_rld1
tmr_ctrl
wuc_32khzosc_status
pd_aux
gp_cfg
gp_out
synt
rc_cal_cfg
vco_band_ovrw
vco_idac_ovrw
vco_ovwr_cfg
pa_bias
vco_cal_cfg
xto26_trim_cal
vco_band_rb
Rev. 0 | Page 87 of 108
ADF7242
Address
0x381
0x389
0x38B
0x395
0x396
0x39B
0x3A7
0x3A8
0x3A9
0x3AA
0x3AE
0x3B2
0x3B4
0x3B6
0x3B7
0x3B8
0x3B9
0x3BA
0x3BC
0x3BF
0x3C4
0x3C7
0x3C8
0x3C9
0x3CA
0x3CB
0x3CC
0x3D2
0x3D3
0x3D4
0x3D5
0x3D6
0x3D7
0x3E0
0x3E3
0x3E6
0x3F0
0x3F3
0x3F4
0x3F7
0x3F8
0x3F9
0x3FA
Register Name
vco_idac_rb
iirf_cfg
dm_cfg1
rxcal0
rxcal1
rxfe_cfg
pa_rr
pa_cfg
Access Mode
R
Description
Readback of the VCO bias current DAC after calibration
BB filter decimation rate
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
Postdemodulator filter bandwidth
Receiver baseband filter calibration word, LSB
Receiver baseband filter calibration word, MSB
Receive baseband filter bandwidth and LNA selection
PA ramp rate
PA output stage current control
External PA bias DAC configuration
External PA interface circuit configuration
ADC readback
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
AGC configuration parameters
OCL system parameters
extpa_cfg
extpa_msc
adc_rbk
agc_cfg1
agc_max
agc_cfg2
agc_cfg3
agc_cfg4
agc_cfg5
agc_cfg6
agc_cfg7
ocl_cfg0
ocl_cfg1
irq1_en0
irq1_en1
irq2_en0
irq2_en1
irq1_src0
irq1_src1
ocl_bw0
ocl_bw1
ocl_bw2
ocl_bw3
ocl_bw4
ocl_bws
ocl_cfg13
gp_drv
bm_cfg
tx_fsk_test
preamble_num_validate
sfd_15_4
afc_cfg
afc_ki_kp
afc_range
afc_read
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
OCL system parameters
Interrupt Mask Set Bits[7:0] of [15:0] for IRQ1
Interrupt Mask Set Bits[15:8] of [15:0] for IRQ1
Interrupt Mask Set Bits[7:0] of [15:0] for IRQ2
Interrupt Mask Set Bits[15:8] of [15:0] for IRQ2
Interrupt Source Bits[7:0] of [15:0] for IRQ
Interrupt Source Bits[15:8] of [15:0] for IRQ
OCL system parameters
OCL system parameters
OCL system parameters
OCL system parameters
OCL system parameters
OCL system parameters
OCL system parameters
GPIO and SPI I/O pads drive strength configuration
Battery monitor threshold voltage setting
TX GFSK/FSK SPORT test mode configuration
Preamble validation
Option to set nonstandard SFD
AFC mode and polarity configuration
AFC ki and kp
AFC range
AFC frequency error readback
Rev. 0 | Page 88 of 108
ADF7242
Table 51. 0x100: ext_ctrl
Bit
Field Name
R/W
Reset Value
Description
[7]
pa_shutdown_mode
R/W
0
PA shutdown mode.
0: fast ramp-down.
1: user defined ramp-down.
[6:5]
4
Reserved
rxen_en
R/W
R/W
0
0
Reserved, set to default.
1: RXEN_GP6 is set high while in the RX state; otherwise, it is low.
0: RXEN_GP6 is under user control (refer to Register gp_out); refer to
Register gp_cfg for restrictions
3
txen_en
R/W
0
1: TXEN_GP5 is set high while in the TX state; otherwise, it is low.
0: TXEN_GP5 is under user control (refer to Register gp_out); refer to
Register gp_cfg for restrictions.
2
extpa_auto_en
Reserved
R/W
R/W
0
0
1: RC enables external PA controller while in the TX state.
0: Register pd_aux, Bit extpa_bias_en (0x31E[4]) is under user control.
Reserved, set to default.
[1:0]
Table 52. 0x102: fsk_preamble
Bit Field Name
R/W
Reset Value Description
Set the number of preamble bytes that is appended at the beginning of a TX
[7:0] Nbtx_preamble_byte
R/W
8
GFSK/FSK frame.
Note that the packet manager automatically transmits another n bytes of
preamble, with n set by MCR Register 0x3F3. Depending on the SWD used, there
may also be additional preamble bits contained in Register 0x10C to Register
0x10E. Refer to the Transmitter in GFSK/FSK Mode section for details.
Table 53. 0x105: cca1
Bit
Field Name R/W Reset Value Description
[7:0] cca_thres
R/W 171
RSSI threshold for CCA. Signed twos complement notation (in dBm). When CCA is completed:
Status Word CCA_RESULT = 1 if Register rrb, Bit rssi_readback (0x30C[7:0]) < cca_thres
Status Word CCA_RESULT = 0 if Register rrb, Bit rssi_readback (0x30C[7:0]) ≥ cca_thres
Table 54. 0x106: cca2
Bit
[7:3]
2
Field Name
R/W
Reset Value Description
Reserved
continuous_cca
R/W
R/W
0
0
Reserved, set to default.
0: continuous CCA off.
1: generate a CCA interrupt every 128 μs.
1
0
rx_auto_cca
Reserved
R/W
R/W
0
0
0: automatic CCA off.
1: generate a CCA interrupt 128 μs after entering the RX state.
Reserved, set to default.
Rev. 0 | Page 89 of 108
ADF7242
Table 55. 0x107: buffercfg
Bit
Field Name
R/W Reset Value Description
7
trx_mac_delay
R/W
0
0: tx_mac_delay (0x10A[7:0]) and rx_mac_delay (0x109[7:0]) enabled.
1: tx_mac_delay (0x10A[7:0]) and rx_mac_delay (0x109[7:0]) disabled.
Reserved, set to default
6
Reserved
R/W
RW
0
0
[5:4] tx_buffer_mode
In IEEE 802.15.4-2006 mode.
0: return to PHY_RDY after frame in TX_BUFFER is transmitted once.
1: cyclic transmission of frame in TX_BUFFER after TX MAC delay with PA ramp-
up/down between packets.
2: reserved.
3: cyclic transmission of frame in TX_BUFFER after TX MAC delay with PA kept
on.
3
2
auto_tx_to_rx_turnaround R//W
auto_rx_to_tx_turnaround R/W
0
0
0
0: as per tx_buffer_mode setting.
1: automatically goes to RX after TX data transmitted.
0: as per rx_buffer_mode setting.
1: automatically goes to TX after RX packet received.
In IEEE 802.15.4-2006 mode.
[1:0] rx_buffer_mode
R/W
0: first frame following a RC_RX command is stored in RX_BUFFER; device
returns to PHY_RDY state after reception of first frame.
1: continuous reception of frames enabled; a new frame overwrites previous
frame.
2: new frames not written to buffer.
3: reserved.
Table 56. 0x108: pkt_cfg
Bit
[7:5]
4
Field Name
R/W
R/W
R/W
Reset Value Description
Reserved
addon_en
0
0
Reserved, set to default.
0: firmware add-on module disabled.
1: firmware add-on module enabled; module must be loaded prior to setting this bit.
3
skip_synt_settle
R/W
0
0: the RF frequency synthesizer calibration and settling phase is performed.
1: skip the RF frequency synthesizer calibration and settling phase. This must only be
used when the continuous packet transmission mode is enabled. Refer to the WUC
Configuration and Operation section.
[2:1]
0
Reserved
auto_fcs_off
R/W
R/W
2
0
Reserved, set to default.
In IEEE 802.15.4-2006 and GFSK/FSK packet mode, the rx_pkt_rcvd interrupt is asserted.
IEEE 802.15.4-2006:
0: receive operation—FCS automatically validated; FCS replaced with RSSI and SQI
values in RX_BUFFER.
Transmit operation—FCS automatically appended to transmitted packet; FCS field in
TX_BUFFER is ignored.
1: receive operation—received FCS is stored in RX_BUFFER without validation.
Transmit operation—FCS field in TX_BUFFER is transmitted.
GFSK/FSK:
0: receive operation—CRC automatically validated.
Transmit operation—CRC automatically appended to transmitted packet; CRC field in
TX_BUFFER is ignored.
1: receive operation—received CRC is stored in RX_BUFFER without validation.
Transmit operation—CRC field in TX_BUFFER is transmitted.
Table 57. 0x109: delaycfg0
Bit
Field Name
R/W
Reset Value Description
192
IEEE 802.15.4-2006 mode: programmable delay from issue of RC_RX command to
[7:0]
rx_mac_delay
R/W
SFD search and for start of RSSI measurement window.
GFSK mode: programmable delay from issue of RC_RX command to SWD search.
Programmable in steps of 1 μs in both modes.
Rev. 0 | Page 90 of 108
ADF7242
Table 58. 0x10A: delaycfg1
Bit
Field Name
R/W
Reset Value Description
[7:0]
tx_mac_delay
R/W
192
IEEE 802.15.4-2006 mode and GFSK mode: programmable delay from issue
of RC_TX command to entering TX state.
Programmable in steps of 1 μs in both modes.
Table 59. 0x10B: delaycfg2
Bit
Field Name
R/W
Reset Value Description
Programmable MAC delay extension. Programmable in steps of 4 μs.
Applies in both RX and TX states
[7:0]
mac_delay_ext
R/W
0
Table 60. 0x10C: sync_word0
Bit
Field Name
R/W
Reset Value Description
[7:0]
sync_word[7:0]
R/W
49
Sync Word Bits[7:0] of [23:0].
Table 61. 0x10D: sync_word1
Bit
Field Name
R/W
Reset Value Description
[7:0]
sync_word[15:8]
R/W
122
Sync Word Bits[15:8] of [23:0].
Table 62. 0x10E: sync_word2
Bit
Field Name
R/W
Reset Value Description
[7:0]
sync_word[23:16]
R/W
170
Sync word Bits[23:16] of [23:0].
Table 63. 0x10F: sync_config
Bit
Field Name
Reserved
sync_tol
R/W
R/W
R/W
Reset Value Description
7
[6:5]
0
0
Reserved, set to default.
Number of bit mismatches allowed: 0 to 3.
4 to 7: reserved.
[4:0]
sync_len
R/W
24
Synchronization word length, which can be from 0 to 24.
0: sync word detection disabled.
25 to 31: reserved.
Table 64. 0x111: fsk_preamble_config
Bit
Field Name
R/W
Reset Value Description
7
6
reserved
R/W
0
0
Unused.
skip_syncword_detect_sport R/W
Bypass SFD detection (GFSK/FSK SPORT mode only).
0: perform sync word detection.
1: skip sync word detection.
5
4
fsk_agc_lock_after_preamble R/W
0
Lock AGC after preamble (GFSK/FSK packet/SPORT modes only).
0: disable AGC lock.
1: enable AGC lock.
Bypass preamble detection and qualification; only search for SWD .
0: enable preamble detection + qualification.
1: disable preamble detection + qualification.
skip_preamble_detect_qual
R/W
R/W
0
[3:0] fsk_preamble_match_level
11
preamble_match
Preamble qualification
0xC
0xB
0xA
0x9
0x1
0x0
Enabled. 0 bit-pairs in error allowed in 12 bit-pairs.
Enabled. 1 bit-pair in error allowed in 12 bit-pairs.
Enabled. 2 bit-pairs in error allowed in 12 bit-pairs.
Enabled. 3 bit-pairs in error allowed in 12 bit-pairs.
Enabled. 11 bit-pairs in error allowed in 12 bit-pairs.
Preamble qualification disabled.
Rev. 0 | Page 91 of 108
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Table 65. 0x13E: rc_cfg
Bit
Field Name
R/W
Reset Value Description
0 Configure packet format:
[7:0]
rc_mode
R/W
0: IEEE 802.15.4-2006 packet mode.
1: reserved.
2: IEEE 802.15.4-2006 receive SPORT mode.
3: GFSK/FSK SPORT mode.
4: GFSK/FSK packet mode.
5 to 255: reserved.
Table 66. 0x300: ch_freq0
Bit
Field Name
R/W
Reset Value Description
[7:0]
ch_freq[7:0]
R/W
128
Channel frequency [Hz]/10 kHz, Bits[7:0] of [23:0].
Table 67. 0x301: ch_freq1
Bit
Field Name
R/W
Reset Value Description
[7:0]
ch_freq[15:8]
R/W
169
Channel frequency [Hz]/10 kHz, Bits[15:8] of [23:0].
Table 68. 0x302: ch_freq2
Bit
Field Name
R/W
Reset Value Description
[7:0]
ch_freq[23:16]
R/W
3
Channel frequency [Hz]/10 kHz, Bits[23:16] of [23:0].
Table 69. 0x304: tx_fd
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:6]
[5:0]
Reserved
tx_freq_dev
0
Reserved, set to default.
50
Transmit frequency deviation = tx_freq_dev × 10 kHz.
Recommended settings:
IEEE 802.15.4: use default setting of 50.
GFSK/FSK:
62.5 kbps to 125 kbps: 6.
250 kbps: 13.
500 kbps: 25.
1000 kbps: 25.
2000 kbps: 50.
Table 70. 0x305: dm_cfg0
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7]
[6:0]
Reserved
discriminator_bw
0
6
Reserved, set to default.
Receive discriminator bandwidth = 3.25 MHz/( RX frequency deviation +
freq_error_max).
Recommended settings:
IEEE 802.15.4: 6 (default).
GFSK/FSK:
50 kbps, 62.5 kbps, 125 kbps: 55.
100 kbps: 107.
250 kbps: 25.
500 kbps, 1000 kbps: 13.
2000 kbps: 6.
Rev. 0 | Page 92 of 108
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Table 71. 0x306: tx_m
Bit
[7:2]
1
Field Name
RC_CONTROLLED
gauss_filt
R/W
R/W
R/W
R/W
Reset Value Description
0
0
1
Controlled by radio controller.
1: GFSK, 0: FSK.
1: enable, 0: disable preemphasis filter. Set for data rate > 250 kbps and
IEEE 802.15.4-2006.
0
preemp_filt
Table 72. 0x30C: rrb
Bit
Field Name
R/W
Reset Value Description
[7:0]
rssi_readback
R
0
Receive input power in dBm; signed twos complement.
Table 73. 0x30D: lrb
Bit
Field Name
R/W
Reset Value Description
[7:0]
sqi_readback
R
0
Signal quality indicator readback value.
Table 74. 0x30E: dr0
Bit
Field Name
R/W
Reset Value Description
[7:0]
data_rate_high
R/W
78
Data rate: 256 × data_rate_high × 100 bps + dr1.
Table 75. 0x30F: dr1
Bit
Field Name
R/W
Reset Value Description
[7:0]
data_rate_low
R/W
32
Data rate: data_rate_low × 100 bps + dr0.
Table 76. 0x313: prampg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:4]
[3:0]
Reserved
pram_page
0
0
Reserved, set to default.
Program PRAM page.
Table 77. 0x314: txpb
Bit
Field Name
R/W
Reset Value Description
[7:0]
tx_pkt_base
R/W
128
Base address of TX_BUFFER in packet RAM.
Table 78. 0x315: rxpb
Bit
Field Name
R/W
Reset Value Description
[7:0]
rx_pkt_base
R/W
0
Base address of RX_BUFFER in packet RAM.
Rev. 0 | Page 93 of 108
ADF7242
Table 79. 0x316: tmr_cfg0
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:3]
[2:0]
Reserved
timer_prescal
0
0
Reserved, set to default.
Divider factor for XTO32K or RCO.
0: ÷1.
1: ÷4.
2: ÷8.
3: ÷16.
4: ÷128.
5: ÷1024.
6: ÷8192.
7: ÷65,536.
Note that this is a write-only register and should be written to prior to writing to
Register tmr_cfg1. Settings become effective only after writing to Register
tmr_cfg1.
Table 80. 0x317: tmr_cfg1
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
7
[6:3]
Reserved
sleep_config
0
0
Reserved, set to default.
1: SLEEP_BBRAM
4: SLEEP_XTO.
5: SLEEP_BBRAM_XTO.
11: SLEEP_BBRAM_RCO.
0, 3, 6 to 10, 12 to 15: reserved.
Refer to note in Register tmr_cfg0.
[2:1]
0
Reserved
wake_on_timeout
R/W
R/W
0
0
Reserved, set to default.
1: enable, 0: disable wake-up on timeout event.
Table 81. 0x318: tmr_rld0
Bit
Field Name
R/W
Reset Value Description
[7:0]
timer_reload[15:8]
R/W
0
Timer reload value, Bits[15:8] of [15:0].
Note that this is a write-only register and should be written to prior to writing to
Register tmr_rld1. Settings become effective only after writing to Register
tmr_rld1.
Table 82. 0x319: tmr_rld1
Bit
Field Name
R/W
Reset Value
Description
[7:0]
timer_reload[7:0]
R/W
0
Timer reload value, Bits[7:0] of [15:0]. Refer to note in Register tmr_rld0.
Table 83. 0x31A: tmr_ctrl
Bit
[7:2]
1
Field Name
R/W
R/W
R/W
Reset Value
Description
Reserved
0
0
Reserved, set to default.
wuc_rc_osc_cal
1: enable.
0: disable 32 kHz RC oscillator calibration.
0
wake_timer_flag_reset R/W
0
Timer flag reset.
0: normal operation
1: reset fields wuc_tmr_prim_toflag and wuc_porflag (0x31B)
Rev. 0 | Page 94 of 108
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Table 84. 0x31B: wuc_32khzosc_status
Bit
[7:6]
5
Field Name
R/W
Reset Value
Description
Reserved
R
0
0
Reserved, set to default.
rc_osc_cal_ready
R
32 kHz RC oscillator calibration (only valid if wuc_rc_osc_cal = 1). Calibration
takes 1 ms.
0: calibration in progress.
1: calibration finished.
4
xosc32_ready
R
0
32 kHz crystal oscillator (only valid if sleep_config (0x317[6:3])= 4 or 5).
0: oscillator not settled.
1: oscillator has settled.
3
2
Reserved
R
R
0
0
Reserved, set to default.
wuc_porflag
Chip cold start event registration.
0: not registered.
1: registered.
1
0
wuc_tmr_prim_toflag
Reserved
R
R
0
0
WUC timeout event registration (the output of a latch triggered by a timeout
event.)
0: not registered.
1: registered.
Reserved, set to default.
Table 85. 0x31E: pd_aux
Bit
Field Name
R/W
Reset Value Description
7
6
5
Reserved
RC_CONTROLLED
battmon_en
R/W
R/W
R/W
0
0
0
Reserved, set to default.
Controlled by radio controller.
1: enable.
0: disable battery monitor.
4
extpa_bias_en
R/W
0
1: enable.
0: disable external PA biasing circuit.
Controlled by radio controller when Register ext_ctrl, Field extpa_auto_en = 1
(0x100[2]).
[3:0]
RC_CONTROLLED
R/W
0
Controlled by radio controller.
Table 86. 0x32C: gp_cfg
Bit
Field Name
R/W
Reset Value Description
0 0: IRQ1, IRQ2 functionality.
[7:0]
gpio_config
R/W
Register gp_out, Bit gpio_dout[6] controls RXEN output.
Register gp_out, Bit gpio_dout[5] controls TXEN output.
1, 4: TRCLK and Data pins active in RX, without gating by frame detection.
2, 5: TRCLK and Data pins activity gated by preamble detection.
3, 6: TRCLK and Data pins activity gated by synchronization word detection.
6: IRQ1, DR, DT, TRFS, TRCLK functionality. Register gp_out, Bit gpio_dout[6]
controls RXEN output.
Register gp_out, Bit gpio_dout[5] controls TXEN output.
7: symbol clock output on TRCLK pin and symbol data output on GP6, GP5, GP1,
and GP0.
103: IRQ1, DR, DT, IRQ2, TRCLK functionality.
Register gp_out, Bit gpio_dout[6] controls RXEN output.
Register gp_out, Bit gpio_dout[5] controls TXEN output.
8 to 102, 104 to 255: reserved.
Rev. 0 | Page 95 of 108
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Table 87. 0x32D: gp_out
Bit
Field Name
R/W
Reset Value Description
0 GPIO output value if Register gp_cfg, Field gpio_config = 4.
[7:0]
gpio_dout
R/W
gpio_dout[7:0] = GP7 to GP0.
If Register ext_ctrl, Bit rxen_en = 1, then Register gp_out,
Bit gpio_dout[6] is controlled by radio controller.
If Register ext_ctrl, Bit txen_en = 1, then Register gp_out,
Bit gpio_dout[5] is controlled by radio controller.
Table 88. 0x335: synt
Bit
Field Name
R/W
Reset Value Description
[7:0]
lock_time
R/W
23
Synthesizer locking timeout period (46 μs). 1 LSB = 2 μs.
Table 89. 0x33D: rc_cal_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:2]
[1:0]
Reserved
skip_rc_cal
15
0
Reserved, set to default.
0: do not skip RC calibration. This calibration is performed only when transitioning
from idle to PHY_RDY.
3: skip RC calibration.
Table 90. 0x353: vco_band_ovrw
Bit
Field Name
R/W
Reset Value Description
[7:0]
vco_band_ovrw_val R/W
0
Overwrite value for the VCO frequency band. Enabled when vco_band_ovrw_en =
1 and Register vco_cal_cfg, Field skip_vco_cal = 15.
Table 91. 0x354: vco_idac_ovrw
Bit
Field Name
R/W
Reset Value Description
Overwrite value for the VCO bias current DAC. Enabled when Register vco_cal_cfg,
Field skip_vco_cal = 15 and vco_idac_ovrw_en = 1.
[7:0]
vco_idac_ovrw_val R/W
0
Table 92. 0x355: vco_ovrw_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:2]
[1]
Reserved
2
Reserved, set to default.
vco_idac_ovrw_en
0
VCO bias current DAC overwrite. Effective only if Register vco_cal_cfg,
Field skip_vco_cal = 15.
0: disable.
1: enable.
[0]
vco_band_ovrw_en R/W
0
VCO frequency band overwrite. Effective only if Register vco_cal_cfg,
Field skip_vco_cal = 15
0: disable.
1: enable.
Table 93. 0x36E: pa_bias
Bit
Field Name
R/W
R/W
R/W
R/W
Reset Value Description
7
[6:1]
0
Reserved
pa_bias_ctrl
Reserved
0
Reserved, set to default.
55
1
Set to 63 if maximum PA output power of 4.8 dBm is required.
Reserved, set to default.
Rev. 0 | Page 96 of 108
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Table 94. 0x36F: vco_cal_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:4]
[3:0]
Reserved
skip_vco_cal
0
9
Reserved, set to default.
9: do not skip VCO calibration.
15: skip VCO calibration
Table 95. 0x371: xto26_trim_cal
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:6]
[5:3]
Reserved
xto26_trim
0
4
Reserved, set to default.
26 MHz crystal oscillator (XOSC26N ) tuning capacitor control word. The load
capacitance is adjusted according to the value of xto26_trim as follows:
0: −4 × 187.5 fF.
1: −3 × 187.5 fF.
2: −2 × 187.5 fF.
3: −1 × 187.5 fF.
4: 0 × 187.5 fF.
5: 1 × 187.5 fF.
6: 2 × 187.5 fF.
7: 3 × 187.5 fF.
[2:0]
Reserved
R/W
0
Reserved, set to default.
Table 96. 0x381: vco_band_rb
Bit
Field Name
R/W
Reset Value Description
[7:2]
vco_band_val_rb
R
0
Readback for the VCO frequency band after calibration
Table 97. 0x381: vco_idac_rb
Bit
Field Name
R/W
Reset Value Description
[7:2]
vco_idac_val_rb
R
0
Read-back of the VCO bias current DAC after calibration
Table 98. 0x389: iirf_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:2]
Reserved
iir_stage2_bw
0
1
Reserved, set to default.
Receive baseband digital filter Stage 2 sampling rate
fs2 = fs1/(2iir_stage2_bw).
For IEEE 802.15.4-2006: set to default.
For GFSK:
62.5 kbps to 250 kbps: 4.
500 kbps: 3.
1000 kbps: 2.
2000 kbps: 1.
[1:0]
iir_stage1_bw
R/W
1
Receive baseband digital filter Stage 1 sampling rate,
fs1 = 13 MHz/(2iir_stage1_bw).
For IEEE 802.15.4-2006: set to default.
For GFSK:
62.5 kbps to 1000 kbps: 2.
2000 kbps: 1.
Rev. 0 | Page 97 of 108
ADF7242
Table 99. 0x38B: dm_cfg1
Bit
Field Name
R/W
Reset Value Description
200 Post demodulator filter BW= postdemod_bw × 15 kHz.
[7:0]
postdemod_bw
R/W
For IEEE 802.15.4-2006: 133.
For GFSK:
62.5 kbps: 8.
125 kbps: 17.
250 kbps: 32.
500 kbps: 61.
1000 kbps: 110.
2000 kbps: 170.
Table 100. 0x395: rxcal0
Bit
Field Name
R/W
Reset Value Description
[7:0]
dcap_ovwrt_low
R/W
0
RXBB filter tuning overwrite word, LSB.
Table 101. 0x396: rxcal1
Bit
[7:2]
1
Field Name
R/W
R/W
R/W
R/W
Reset Value Description
Reserved
dcap_ovwrt_en
dcap_ovwrt_high
2
0
0
Reserved, set to default.
RXBB filter tuning overwrite word enable.
RXBB filter tuning overwrite word, MSB.
0
Table 102. 0x39B: rxfe_cfg
Bit
Field Name
Reserved
lna_sel
R/W
R/W
R/W
Reset Value Description
[7:5]
[4]
0
1
Reserved, set to default.
Receive:
0: use LNA1.
1: use LNA2.
[3:0]
rxbb_bw_ana
R/W
13
RXBB analog filter bandwidth:
15 = 1186 kHz
14 = 1086 kHz
13 = 1029 kHz
12 = 991 kHz
11 = 927 kHz
10 = 867 kHz
9 = 797 kHz
8 = 730 kHz
7 = 655 kHz
6 = 555 kHz
For IEEE 802.15.4-2006 mode: set to default.
For GFSK:
62.5 kbps to 1000 kbps: set to 6.
2000 kbps: set to 13.
Table 103. 0x3A7: pa_rr
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:3]
[2:0]
Reserved
pa_ramp_rate
0
7
Reserved, set to default.
PA ramp rate:
2pa_rr.pa_ramp_rate × 2.4 ns per PA power step.
Rev. 0 | Page 98 of 108
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Table 104. 0x3A8: pa_cfg
Bit
Field Name
R/W
R/W
R/W
R/W
Reset Value Description
7
[6:5]
[4:0]
Reserved
Reserved
pa_bridge_dbias
0
Reserved, set to default.
0
Set to default.
13
Set to 21 if output power of 4.8 dBm is required from PA.
Table 105. 0x3A9: extpa_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
Reserved
extpa_bias
0
0
Reserved, set to default.
If Register extpa_msc, Field extpa_bias_mode = 1, 2, 3, or 4,
PABIAOP_ATB4 pin DAC current = 80 μA − 2.58 μA × extpa_bias.
If Register extpa_msc, Field extpa_bias_mode = 5 or 6,
PAVSUP_ATB3 pin servo current set point = 22 mA − 0.349 mA × extpa_bias.
Table 106. 0x3AA: extpa_msc
Bit
Field Name
R/W
Reset Value Description
[7:4]
pa_pwr
R/W
15
PA output power after ramping phase:
3: minimum power.
15: maximum power.
Nominal power step size 2 dB per LSB.
3
extpa_bias_src
R/W
R/W
0
1
0: select RBIAS-referred reference current.
1: select band gap-referred reference current.
External PA interface configuration:
[2:0]
extpa_bias_mode
0: PAVSUP_ATB3 = on; PABIAOP_ATB4 = floating.
1: PAVSUP_ATB3 = on; PABIAOP_ATB4 = current source.
2: PAVSUP_ATB3 = on; PABIAOP_ATB4 = current sink.
3: PAVSUP_ATB3 = off; PABIAOP_ATB4 = current source.
4: PAVSUP_ATB3 = off; PABIAOP_ATB4 = current sink.
5: PAVSUP_ATB3 = on; PABIAOP_ATB4 = positive servo output.
6: PAVSUP_ATB3 = on; PABIAOP_ATB4 = negative servo output.
7: reserved.
Table 107. 0x3AE: adc_rbk
Bit
Field Name
Reserved
adc_out
R/W
R
R
Reset Value Description
[7:6]
[5:0]
0
0
Ignore.
ADC output code.
Table 108. 0x3B2: agc_cfg1
Bit
Field Name
R/W
R/W
R/W
R/W
R/W
Reset Value Description
7
Reserved
0
1
8
0
Reserved, set to default.
[6:5]
[4:1]
0
agc_lna_hyst
agc_lna_thres
agc_lock
Hysteresis in terms of PGA attenuation steps for LNA gain transitions.
Sets number of PGA attenuation steps prior to first LNA attenuation step.
0: enable, 1: freeze AGC.
Table 109. 0x3B4: agc_max
Bit
Field Name
R/W
Reset Value Description
[7:6]
[5:3]
Reserved
agc_sat_thres_offs R/W
R/W
2
2
Reserved, set to default.
ADC saturation detection threshold offset from full scale; the AGC enters slewing
mode when this threshold is exceeded.
[2:0]
Reserved R/W
0
Reserved, set to default.
Rev. 0 | Page 99 of 108
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Table 110. 0x3B6: agc_cfg2
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
7
[6:0]
Reserved
agc_thres_hi
0
Reserved, set to default.
46
AGC upper RSSI trigger threshold.
For IEEE 802.15.4-2006: set to default.
For GFSK mode: set to 55.
Table 111. 0x3B7: agc_cfg3
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
7
[6:0]
Reserved
agc_target
0
Reserved, set to default.
35
AGC RSSI active state target value.
For IEEE 802.15.4-2006: set to default.
For GFSK mode: set to 42.
Table 112. 0x3B8: agc_cfg4
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
7
[6:0]
Reserved
agc_thres_lo
0
Reserved, set to default.
24
AGC lower RSSI trigger threshold.
For IEEE 802.15.4-2006: set to default.
For GFSK mode: set to 29.
Table 113. 0x3B9: agc_cfg5
Bit
Field Name
R/W
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:2]
[1:0]
Reserved
rssi_offs
rssi_avg_time
0
4
3
Set to 0.
RSSI offset adjust, rssi_offs is added to Register rrb, Field rssi_readback.
RSSI averaging time; default per IEEE 802.15.4-2006; refer to the Baseband Filter
section for further details.
Table 114. 0x3BA: agc_cfg6
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:6]
[5:3]
Reserved
agc_filt2_tavg2
0
5
Reserved, set to default.
AGC postfilter averaging time.
For IEEE 802.15.4-2006: per default.
For GFSK: set to 4.
[2:0]
agc_filt2_tavg1
R/W
5
AGC postfilter averaging time for LNA transition.
For IEEE 802.15.4-2006: per default.
For GFSK/FSK: set to 4.
Table 115. 0x3BC: agc_cfg7
Bit
Field Name
R/W Reset Value
R/W
Description
7
[6:3]
[2:0]
Reserved
agc_ndelay_steady R/W 15
agc_egain_exp R/W
0
Reserved, set to default.
AGC agc_steady delay counter.
AGC integrator gain.
1
Rev. 0 | Page 100 of 108
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Table 116. 0x3BF: ocl_cfg0
Bit Field Name
[7:2] Reserved
R/W
Reset Value
Description
R/W
0
Reserved, set to default.
1: enable
1
ocl_en_gclna_ocl_hibw_state R/W
0: disable OCL wide bandwidth mode after LNA gain changes.
1
0
0
IEEE 802.15.4 mode.
GFSK/FSK mode.
Reserved, set to default.
0
Reserved
R/W
Table 117. 0x3C4: ocl_cfg1
Bit
Field Name
R/W
Reset Value
Description
[7:0]
ocl_fsk_lock_timeout
R/W
5
For IEEE 802.15.4-2006: per default. For GFSK/FSK: set to 7.
Table 118. 0x3C7: irq1_en0
Bit
Field Name
Reserved
Reserved
batt_alert
por
rc_ready
wakeup
powerup
Reserved
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
1
0
Set to 0.
Set to 0.
Battery monitor interrupt.
Power-on reset event.
Radio controller ready to accept new command.
Timer has timed out.
Chip is ready for access.
Set to 0.
Table 119. 0x3C8: irq1_en1
Bit
Field Name
Reserved
Reserved
Reserved
tx_pkt_sent
rx_pkt_rcvd
tx_sfd
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Set to 0.
Set to 0.
Set to 0.
Packet transmission complete.
Packet received in RX_BUFFER.
SFD/SWD was transmitted.
SFD/SWD was detected.
CCA_RESULT in status word is valid.
rx_sfd
cca_complete
Table 120. 0x3C9: irq2_en0
Bit
Field Name
Reserved
Reserved
batt_alert
por
rc_ready
wakeup
powerup
Reserved
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
1
0
Set to 0.
Set to 0.
Battery monitor interrupt.
Power-on reset event.
Radio controller ready to accept new command.
Timer has timed out.
Chip is ready for access.
Set to 0.
Rev. 0 | Page 101 of 108
ADF7242
Table 121. 0x3CA: irq2_en1
Bit
Field Name
Reserved
Reserved
Reserved
tx_pkt_sent
rx_pkt_rcvd
tx_sfd
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Set to 0.
Set to 0.
Set to 0.
Packet transmission complete.
Packet received in RX_BUFFER.
SFD/SWD was transmitted.
SFD/SWD was detected.
CCA_RESULT in status word is valid.
rx_sfd
cca_complete
Table 122. 0x3CB: irq_src0
Bit
Field Name
Reserved
Reserved
batt_alert
por
rc_ready
wakeup
powerup
Reserved
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Set to 0.
Set to 0.
Battery monitor interrupt.
Power-on reset event.
Radio controller ready to accept new command.
Timer has timed out.
Chip is ready for access.
Set to 0.
Table 123. 0x3CC: irq_src1
Bit
Field Name
Reserved
Reserved
Reserved
tx_pkt_sent
rx_pkt_rcvd
tx_sfd
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value Description
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Set to 0.
Set to 0.
Set to 0.
Packet transmission complete.
Packet received in RX_BUFFER.
SFD/SWD was transmitted.
SFD/SWD was detected.
CCA_RESULT in status word is valid.
rx_sfd
cca_complete
Table 124. 0x3D2: ocl_bw0
Bit
Field Name
Reserved
ocl_bw0
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 26.
27
Table 125. 0x3D3: ocl_bw1
Bit
Field Name
Reserved
ocl_bw1
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 25.
26
Table 126. 0x3D4: ocl_bw2
Bit
Field Name
Reserved
ocl_bw2
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
2
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 30.
Rev. 0 | Page 102 of 108
ADF7242
Table 127. 0x3D5: ocl_bw3
Bit
Field Name
Reserved
ocl_bw3
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
3
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 30.
Table 128. 0x3D6: ocl_bw4
Bit
Field Name
Reserved
ocl_bw4
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
2
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 30.
Table 129. 0x3D7: ocl_bws
Bit
Field Name
Reserved
ocl_bw
R/W
R/W
R/W
Reset Value Description
[7:5]
[4:0]
0
0
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 0.
Table 130. 0x3E0: ocl_cfg13
Bit
[7:2]
1
Field Name
R/W
R/W
R/W
R/W
Reset Value Description
Reserved
ocl_sosi_en
Reserved
60
1
Reserved, set to default.
For IEEE 802.15.4-2006: set to default. For GFSK/FSK: set to 0.
Reserved, set to default.
0
0
Table 131. 0x3E3: gp_drv
Bit
Field Name
R/W
R/W
R/W
Reset Value Description
[7:4]
[3:2]
Reserved
gpio_slew
0
0
Reserved, set to default.
GPIO and SPI slew rate.
0: very slow.
1: slow.
2: very fast.
3: fast.
[1:0]
gpio_drive
R/W
0
GPIO and SPI drive strength.
0: 4 mA.
1: 8 mA.
2: >8 mA.
3: reserved.
Table 132. 0x3E6: bm_cfg
Bit
Field Name
R/W
R/W
R/W
Reset Value
Description
7:5]
[4:0]
Reserved
battmon_voltage
0
0
Reserved, set to default.
Battery monitor trip voltage:
1.7 V + 62 mV × battmon_voltage; the batt_alert interrupt is asserted when
VDD_BAT drops below the trip voltage.
Table 133. 0x3F0: tx_fsk_test
Bit
[7:4]
3
2
1
Field Name
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
Description
Reserved
2
0
0
0
0
Reserved, set to default.
zero_only
one_only
carrier_only
Reserved
Transmit 0 only (fCH − fDEV) in GFSK/FSK SPORT mode.
Transmit 1 only (fCH + fDEV) in GFSK/FSK SPORT mode.
Transmits unmodulated tone at the programmed frequency fCH.
Reserved, set to default.
0
Rev. 0 | Page 103 of 108
ADF7242
Table 134. 0x3F3: preamble_num_validate
Bit
Field Name
R/W
Reset Value
Description
[7]
[6:0]
Reserved
num_preamble_bytes R/W
R/W
0
5
Reserved, set to default.
Number of preamble bytes required for preamble validation.
Table 135. 0x3F4: sfd_15_4
Bit
Field Name
R/W
R/W
R/W
Reset Value
Description
[7:4]
[3:0]
sfd_symbol_2
sfd_symbol_1
10
7
Symbol 2 of SFD note: IEEE 802.15.4-2006 requires SFD1 = 10.
Symbol 1 of SFD note: IEEE 802.15.4-2006 requires SFD1 = 7.
Table 136. 0x3F7: afc_cfg
Bit
Field Name
R/W
R/W
R/W
R/W
Reset Value
Description
[7:3]
[2]
[1:0]
Reserved
afc_polarity
afc_mode
0
0
0
Reserved, set to default.
Set AFC polarity. Set to 1.
00: lock AFC.
01: reserved.
10: AFC is free running.
11: lock AFC on preamble detection.
Table 137. 0x3F8: afc_ki_kp
Bit
Field Name
R/W
Reset Value Description
[7:4]
afc_kp
R/W
0
Sets the AFC PI controller proportional gain.
For IEEE 802.15.4-2006: not used.
For GFSK: set to 9.
[3:0]
afc_ki
R/W
0
Sets the AFC PI controller integral gain.
For IEEE 802.15.4-2006: not used.
For GFSK: set to 9.
Table 138. 0x3F9: afc_range
Bit
Field Name
R/W
Reset Value Description
Limits the AFC pull-in range. Should be set to half the receive baseband filter
bandwidth. AFC pull-in range is max_afc_range in kHz.
[7:0]
max_afc_range
R/W
0
Table 139. 0x3FA: afc_read
Bit
Field Name
R/W
Reset Value Description
0 Frequency error readback. Frequency error: 1 kHz/LSB.
[7:0]
afc_freq_error
R/W
Rev. 0 | Page 104 of 108
ADF7242
OUTLINE DIMENSIONS
5.10
5.00 SQ
4.90
0.30
0.25
0.18
PIN 1
INDICATOR
PIN 1
INDICATOR
25
32
24
1
0.50
BSC
3.45
3.30 SQ
3.15
EXPOSED
PAD
17
8
16
9
0.50
0.40
0.30
0.25 MIN
TOP VIEW
BOTTOM VIEW
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
0.80
0.75
0.70
0.05 MAX
0.02 NOM
SECTION OF THIS DATA SHEET.
COPLANARITY
0.08
0.20 REF
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-220-WHHD.
Figure 119. 32-Lead Lead Frame Chip Scale Package [LFCSP_WQ]
5 mm × 5 mm Body, Very Thin Quad
(CP-32-13)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature Range
Package Description
Package Option
CP-32-13
CP-32-13
ADF7242BCPZ
−40°C to +85°C
−40°C to +85°C
32-Lead Lead Frame Chip Scale Package [LFCSP_WQ]
32-Lead Lead Frame Chip Scale Package [LFCSP_WQ]
Evaluation Platform Daughterboard
ADF7242BCPZ-RL
EVAL-ADF7242DB1Z
EVAL-ADF7XXXMB3Z
Evaluation Platform Motherboard
1 Z = RoHS Compliant Part.
Rev. 0 | Page 105 of 108
ADF7242
NOTES
Rev. 0 | Page 106 of 108
ADF7242
NOTES
Rev. 0 | Page 107 of 108
ADF7242
NOTES
©2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D08912-0-7/10(0)
Rev. 0 | Page 108 of 108
相关型号：
ADF7242BCPZ
SPECIALTY TELECOM CIRCUIT, QCC32, 5 X 5 MM, ROHS COMPLIANT, MO-220WHHD, LFCSP-32
ROCHESTER
ADF7901BRUZ
TELECOM, CELLULAR, RF AND BASEBAND CIRCUIT, PDSO24, LEAD FREE, MO-153AD, TSSOP-24
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