ADS7138-Q1_V01 [TI]

ADS7138-Q1 Small, 8-Channel, 12-Bit ADC With I2C Interface, GPIOs, and CRC;
ADS7138-Q1_V01
型号: ADS7138-Q1_V01
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
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ADS7138-Q1 Small, 8-Channel, 12-Bit ADC With I2C Interface, GPIOs, and CRC

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ADS7138-Q1
SBAS977A – MAY 2020 – REVISED OCTOBER 2020  
ADS7138-Q1 Small, 8-Channel, 12-Bit ADC With I2C Interface, GPIOs, and CRC  
1 Features  
2 Applications  
AEC-Q100 qualified for automotive applications:  
Temperature grade 1: –40°C to +125°C, TA  
Small package size:  
Camera modules without processing  
Automotive center information displays  
Automotive cluster displays  
– 3-mm × 3-mm WQFN  
– Wettable flanks for visual inspection of solder  
joints  
8 channels configurable as any combination of:  
– Up to 8 analog inputs, digital inputs, or digital  
outputs  
GPIOs for I/O expansion:  
– Open-drain, push-pull digital outputs  
Wide operating ranges:  
3 Description  
The ADS7138-Q1 is an easy-to-use, 8-channel,  
multiplexed, 12-bit, successive approximation register  
analog-to-digital converter (SAR ADC). The eight  
channels can be independently configured as either  
analog inputs, digital inputs, or digital outputs. The  
device has an internal oscillator for ADC conversion  
processes.  
The ADS7138-Q1 communicates via an  
I
2C-  
– AVDD: 2.35 V to 5.5 V  
compatible interface and operates in either  
autonomous or single-shot conversion mode. The  
ADS7138-Q1 implements analog watchdog function  
by event-triggered interrupts per channel using a  
digital window comparator with programmable high  
and low thresholds, hysteresis, and an event counter.  
The ADS7138-Q1 has a built-in cyclic redundancy  
check (CRC) for data read/write operations and the  
power-up configuration.  
– DVDD: 1.65 V to 5.5 V  
– –40°C to +125°C temperature range  
CRC for read/write operations:  
– CRC on data read/write  
– CRC on power-up configuration  
I2C interface:  
– Up to 3.4 MHz (high-speed mode)  
– 8 configurable I2C addresses  
Programmable averaging filters:  
– Programmable sample size for averaging  
– Averaging with internal conversions  
– 16-bit resolution for average output  
Turbo comparator mode with speeds up to  
3.2 MSPS  
Device Information (1)  
PART NAME  
PACKAGE  
BODY SIZE (NOM)  
ADS7138-Q1  
WQFN (16)  
3.00 mm × 3.00 mm  
(1) For all available packages, see the orderable addendum at  
the end of the datasheet.  
Example System Architecture  
Device Block Diagram  
AVDD  
DECAP  
VCC  
AVDD  
High/Low Threshold  
Hysteresis  
DVDD  
OVP  
AIN0 / GPIO0  
AIN1 / GPIO1  
AIN2 / GPIO2  
AIN3 / GPIO3  
AIN4 / GPIO4  
AIN5 / GPIO5  
AIN6 / GPIO6  
AIN7 / GPIO7  
ALERT  
Programmable  
Averaging Filter  
ADC  
Digital Window  
Comparator  
MUX  
ADC  
GPIO  
OCP  
MUX  
ADDR  
Sequencer  
Pin CFG  
I2C Interface  
CRC  
SDA  
SCL  
GPO Write  
GPI Read  
OVP: Over voltage protection  
OCP: Over current protection  
GND  
ADS7138-Q1 Block Diagram and Applications  
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,  
intellectual property matters and other important disclaimers. PRODUCTION DATA.  
 
 
 
ADS7138-Q1  
SBAS977A – MAY 2020 – REVISED OCTOBER 2020  
www.ti.com  
Table of Contents  
1 Features............................................................................1  
2 Applications.....................................................................1  
3 Description.......................................................................1  
4 Revision History.............................................................. 2  
5 Device Comparison Table...............................................3  
6 Pin Configuration and Functions...................................4  
Pin Functions.................................................................... 5  
7 Specifications.................................................................. 6  
7.1 Absolute Maximum Ratings ....................................... 6  
7.2 ESD Ratings .............................................................. 6  
7.3 Recommended Operating Conditions ........................6  
7.4 Thermal Information ...................................................7  
7.5 Electrical Characteristics ............................................8  
7.6 I2C Timing Requirements ...........................................9  
7.7 Timing Requirements .................................................9  
7.8 I2C Switching Characteristics ...................................10  
7.9 Switching Characteristics .........................................10  
7.10 Timing Diagram.......................................................11  
7.11 Typical Characteristics............................................ 12  
8 Detailed Description......................................................16  
8.1 Overview...................................................................16  
8.2 Functional Block Diagram.........................................16  
8.3 Feature Description...................................................17  
8.4 Device Functional Modes..........................................29  
8.5 Programming............................................................ 33  
8.6 ADS7138-Q1 Registers............................................ 36  
9 Application and Implementation..................................77  
9.1 Application Information............................................. 77  
9.2 Typical Applications.................................................. 77  
10 Power Supply Recommendations..............................79  
10.1 AVDD and DVDD Supply Recommendations.........79  
11 Layout...........................................................................80  
11.1 Layout Guidelines................................................... 80  
11.2 Layout Example...................................................... 80  
12 Device and Documentation Support..........................81  
12.1 Receiving Notification of Documentation Updates..81  
12.2 Support Resources................................................. 81  
12.3 Trademarks.............................................................81  
12.4 Electrostatic Discharge Caution..............................81  
12.5 Glossary..................................................................81  
13 Mechanical, Packaging, and Orderable  
Information.................................................................... 81  
4 Revision History  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision * (May 2020) to Revision A (October 2020)  
Page  
Changed document status from advance information to production data.......................................................... 1  
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5 Device Comparison Table  
ZERO-CROSSING-DETECT  
ROOT-MEAN-SQUARE  
(RMS) MODULE  
PART NUMBER  
DESCRIPTION  
CRC MODULE  
(ZCD) MODULE  
ADS7128  
ADS7138  
Yes  
Yes  
Yes  
Yes  
No  
No  
Yes  
No  
No  
8-channel, 12-bit ADC with  
I2C interface and GPIOs  
ADS7138-Q1  
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6 Pin Configuration and Functions  
AIN2/GPIO2  
AIN3/GPIO3  
AIN4/GPIO4  
AIN5/GPIO5  
1
2
3
4
12  
11  
10  
9
ALERT  
ADDR  
DVDD  
GND  
Thermal  
Pad  
Not to scale  
Figure 6-1. RTE Package, 16-Pin WQFN, Top View  
Table 6-1. Pin Functions  
PIN  
NAME  
FUNCTION(1)  
DESCRIPTION  
NO.  
Channel 0; configurable as either an analog input (default) or a general-purpose  
input/output (GPIO).  
AIN0/GPIO0  
15  
AI, DI, DO  
AIN1/GPIO1  
AIN2/GPIO2  
AIN3/GPIO3  
AIN4/GPIO4  
AIN5/GPIO5  
AIN6/GPIO6  
AIN7/GPIO7  
16  
1
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
Channel 1; configurable as either an analog input (default) or a GPIO.  
Channel 2; configurable as either an analog input (default) or a GPIO.  
Channel 3; configurable as either an analog input (default) or a GPIO.  
Channel 4; configurable as either an analog input (default) or a GPIO.  
Channel 5; configurable as either an analog input (default) or a GPIO.  
Channel 6; configurable as either an analog input (default) or a GPIO.  
Channel 7; configurable as either an analog input (default) or a GPIO.  
2
3
4
5
6
Input for selecting the device I2C address.  
Connect a resistor to this pin from DECAP pin or GND to select one of the eight  
addresses.  
ADDR  
11  
AI  
ALERT  
AVDD  
12  
7
Digital output  
Supply  
Open-drain (default) or push-pull output for the digital comparator.  
Analog supply input, also used as the reference voltage to the ADC; connect a  
1-µF decoupling capacitor to GND.  
Connect a1-µF decoupling capacitor between the DECAP and GND pins for the  
internal power supply.  
DECAP  
DVDD  
GND  
8
10  
9
Supply  
Supply  
Supply  
Digital I/O supply voltage; connect a 1-µF decoupling capacitor to GND.  
Ground for the power supply; all analog and digital signals are referred to this  
pin voltage.  
SDA  
14  
13  
DI, DO  
DI  
Serial data input or output for the I2C interface.  
Serial clock for the I2C interface.  
SCL  
Thermal pad  
Supply  
Exposed thermal pad; connect to GND.  
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Pin Functions  
PIN  
FUNCTION(1)  
DESCRIPTION  
NAME  
NO.  
Channel 0; configurable as either an analog input (default) or a general-purpose  
input/output (GPIO).  
AIN0/GPIO0  
15  
AI, DI, DO  
AIN1/GPIO1  
AIN2/GPIO2  
AIN3/GPIO3  
AIN4/GPIO4  
AIN5/GPIO5  
AIN6/GPIO6  
AIN7/GPIO7  
16  
1
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
AI, DI, DO  
Channel 1; configurable as either an analog input (default) or a GPIO.  
Channel 2; configurable as either an analog input (default) or a GPIO.  
Channel 3; configurable as either an analog input (default) or a GPIO.  
Channel 4; configurable as either an analog input (default) or a GPIO.  
Channel 5; configurable as either an analog input (default) or a GPIO.  
Channel 6; configurable as either an analog input (default) or a GPIO.  
Channel 7; configurable as either an analog input (default) or a GPIO.  
2
3
4
5
6
Input for selecting the device I2C address.  
Connect a resistor to this pin from DECAP pin or GND to select one of the eight  
addresses.  
ADDR  
11  
AI  
ALERT  
AVDD  
12  
7
Digital output  
Supply  
Open-drain (default) or push-pull output for the digital comparator.  
Analog supply input, also used as the reference voltage to the ADC; connect a  
1-µF decoupling capacitor to GND.  
Connect a1-µF decoupling capacitor between the DECAP and GND pins for the  
internal power supply.  
DECAP  
DVDD  
GND  
8
10  
9
Supply  
Supply  
Supply  
Digital I/O supply voltage; connect a 1-µF decoupling capacitor to GND.  
Ground for the power supply; all analog and digital signals are referred to this  
pin voltage.  
SDA  
14  
13  
DI, DO  
DI  
Serial data input or output for the I2C interface.  
Serial clock for the I2C interface.  
SCL  
Thermal pad  
Supply  
Exposed thermal pad; connect to GND.  
(1) AI = analog input, DI = digital input, and DO = digital output.  
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7 Specifications  
7.1 Absolute Maximum Ratings  
over operating ambient temperature range (unless otherwise noted)(1)  
MIN  
–0.3  
–0.3  
MAX  
5.5  
UNIT  
V
DVDD to GND  
AVDD to GND  
5.5  
V
AINx/GPOx(3)  
GND – 0.3 AVDD + 0.3  
V
ADDR  
GND – 0.3  
GND – 0.3  
–10  
2.1  
5.5  
10  
V
Digital inputs  
V
Current through any pin except supply pins, SCL, and SDA(2)  
mA  
°C  
°C  
Junction temperature, TJ  
–40  
125  
150  
Storage temperature, Tstg  
–60  
(1) Stresses beyond those listed under Absolute Maximum Rating may cause permanent damage to the device. These are stress ratings  
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under  
Recommended Operating Condition. Exposure to absolute-maximum-rated conditions for extended periods may affect device  
reliability.  
(2) Pin current must be limited to 10mA or less.  
(3) AINx/GPIOx refers to pins 1, 2, 3, 4, 5, 6, 15, and 16.  
7.2 ESD Ratings  
VALUE  
UNIT  
Human-body model (HBM), per AEC Q100-002(1)  
±2000  
Charged-device model (CDM), per AEC Q100-011; corner pins (1,  
4, 5, 8, 9, 12, 13, 16)  
V(ESD)  
Electrostatic discharge  
±750  
±500  
V
Charged-device model (CDM), per AEC Q100-011; all other pins  
(1) AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification  
7.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
POWER SUPPLY  
AVDD  
DVDD  
Analog supply voltage  
Digital supply voltage  
2.35  
1.65  
3.3  
3.3  
5.5  
5.5  
V
V
ANALOG INPUTS  
FSR  
VIN  
Full-scale input range  
Absolute input voltage  
AINX (1) - GND  
AINX - GND  
0
AVDD  
V
V
–0.1  
AVDD + 0.1  
TEMPERATURE RANGE  
TA Ambient temperature  
–40  
25  
125  
(1) AINx refers to AIN0, AIN1, AIN2, AIN3, AIN4, AIN5, AIN6, and AIN7.  
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7.4 Thermal Information  
ADS7138-Q1  
THERMAL METRIC(1)  
RTE (WQFN)  
16 PINS  
49.7  
UNIT  
RθJA  
Junction-to-ambient thermal resistance  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJC(top)  
RθJB  
53.4  
24.7  
ΨJT  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (bottom) thermal resistance  
1.3  
ΨJB  
24.7  
RθJC(bot)  
9.3  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report.  
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7.5 Electrical Characteristics  
at AVDD = 2.35 V to 5 V, DVDD = 1.65 V to 5.5 V, and maximum throughput (unless otherwise noted); minimum and  
maximum values at TA = –40°C to +125°C; typical values at TA = 25°C.  
PARAMETER  
ANALOG INPUTS  
CSH Sampling capacitance  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
12  
pF  
DC PERFORMANCE  
Resolution  
No missing codes  
12  
±0.2  
±0.45  
±0.4  
±1  
bits  
0.75 LSB  
1.5 LSB  
DNL  
INL  
Differential nonlinearity  
–0.75  
–1.5  
–2  
Integral nonlinearity  
Input offset error  
V(OS)  
Post offset calibration  
Post offset calibration  
2
LSB  
Input offset thermal drift  
Gain error  
ppm/°C  
GE  
–0.065  
±0.025  
±1  
0.065 %FSR  
ppm/°C  
Gain error thermal drift  
AC PERFORMANCE  
AVDD = 5 V, fIN = 2 kHz  
AVDD = 3 V, fIN = 2 kHz  
AVDD = 5 V, fIN = 2 kHz  
AVDD = 3 V, fIN = 2 kHz  
fIN = 2 kHz  
70  
69.8  
71.2  
70.5  
72.8  
72.4  
73  
SINAD Signal-to-noise + distortion ratio  
dB  
dB  
SNR  
THD  
Signal-to-noise ratio  
72.5  
–85  
91  
Total harmonic distortion  
dB  
dB  
SFDR Spurious-free dynamic range  
fIN = 2 kHz  
100-kHz signal applied on any OFF  
channel and measured on ON the  
channel  
Crosstalk  
–100  
dB  
DECAP Pin  
CDECAP Decoupling capacitor on DECAP pin  
Voltage output on DECAP pin  
DIGITAL INPUT/OUTPUT (SCL, SDA)  
0.1  
1
4.7  
µF  
V
CDECAP = 1 µF  
1.8  
VIH  
VIL  
Input high logic level  
Input low logic level  
All I2C modes  
0.7 x DVDD  
DVDD  
V
V
All I2C modes  
–0.3  
0
0.3 x DVDD  
Sink current = 2 mA, DVDD > 2 V  
Sink current = 2 mA, DVDD ≤ 2 V  
VOL = 0.4 V, standard and fast Mode  
VOL = 0.6 V, fast mode  
0.4  
VOL  
Output low logic level  
V
0
0.2 x DVDD  
3
6
IOL  
Low-level output current (sink)  
mA  
VOL = 0.4 V, fast mode plus  
20  
GPIOs  
VIH  
Input high logic level  
Input low logic level  
Input leakge current  
0.7 x AVDD  
–0.3  
AVDD + 0.3  
0.3 x AVDD  
100  
V
V
VIL  
GPIO configured as input  
10  
nA  
GPO_DRIVE_CFG = push-pull, I  
SOURCE = 2 mA  
VOH  
Output high logic level  
0.8 x AVDD  
0
AVDD  
V
VOL  
IOH  
IOL  
Output low logic level  
ISINK = 2 mA  
0.2 x AVDD  
V
Output high source current  
Output low sink current  
VOH > 0.7 x AVDD  
VOL < 0.3 x AVDD  
5
5
mA  
mA  
DIGITAL OUTPUT (ALERT)  
GPO_DRIVE_CFG = push-pull, I  
SOURCE = 2 mA  
VOH  
VOL  
Output high logic level  
Output low logic level  
0.8 x DVDD  
0
DVDD  
V
V
ISINK = 2 mA  
0.2 x DVDD  
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7.5 Electrical Characteristics (continued)  
at AVDD = 2.35 V to 5 V, DVDD = 1.65 V to 5.5 V, and maximum throughput (unless otherwise noted); minimum and  
maximum values at TA = –40°C to +125°C; typical values at TA = 25°C.  
PARAMETER  
Output high sink current  
Output low sink current  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
IOH  
IOL  
VOH > 0.7 x DVDD  
5
5
mA  
mA  
VOL < 0.3 x DVDD  
POWER SUPPLY CURRENTS  
I2C high-speed mode, AVDD = 5 V  
I2C fast mode plus, AVDD = 5 V  
I2C fast mode, AVDD = 5 V  
130  
45  
25  
12  
7
210  
85  
46  
26  
20  
IAVDD  
Analog supply current  
µA  
I2C standard mode, AVDD = 5 V  
No conversion, AVDD = 5 V  
7.6 I2C Timing Requirements  
MODE(2)  
STANDARD, FAST, AND  
FAST MODE PLUS  
HIGH-SPEED MODE  
UNIT  
MIN  
MAX  
MIN  
MAX  
3.4  
fSCL  
SCL clock frequency(1)  
1
MHz  
ns  
tSU;STA  
Setup time for a repeated START condition  
260  
260  
160  
160  
Hold time after repeated START condition.  
After this period, the first clock is generated.  
tHD;STA  
ns  
tLOW  
Low period of the SCL clock pin  
High period for the SCL clock pin  
Data in setup time  
500  
260  
50  
160  
60  
10  
0
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
ns  
tHIGH  
tSU;DAT  
tHD;DAT  
Data in hold time  
0
SCL rise time, standard mode  
SCL rise time, fast mode  
1000  
300  
120  
1000  
300  
120  
80  
tR  
SCL rise time, fast mode plus  
SCL rise time, high-speed mode  
SCL fall time, standard mode  
SCL fall time, fast mode  
300  
300  
120  
300  
300  
120  
80  
tF  
SCL fall time, fast mode plus  
SCL fall time, high-speed mode  
STOP condition hold time  
Bus free time before new transmission  
tSU;STO  
tBUF  
260  
500  
60  
300  
(1) Bus load (CB) consideration; CB ≤ 400 pF for fSCL ≤ 1 MHz; CB < 100 pF for fSCL = 3.4 MHz.  
(2) The device supports standard, full-speed, and fast modes by default on power-up. For selecting high-speed mode refer to the section  
on Configuring the Device for High-Speed I2C Mode .  
7.7 Timing Requirements  
at AVDD = 2.35 V to 5 V, DVDD = 1.65 V to 5.5 V, and maximum throughput (unless otherwise noted); minimum and  
maximum values at TA = –40°C to +125°C ; typical values at TA = 25°C.  
MIN  
300  
90  
MAX  
UNIT  
Acquisition time (CONV_MODE = 00b or 01b)  
tACQ  
ns  
Acquisition time in turbo comparator mode (CONV_MODE = 10b)  
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7.8 I2C Switching Characteristics  
MODE  
STANDARD, FAST, AND  
HIGH-SPEED MODE  
MIN MAX  
UNIT  
FAST MODE PLUS  
MIN  
MAX  
120  
450  
450  
450  
1400  
50  
tF  
Fall time for SDA  
80  
200  
200  
200  
1000  
10  
ns  
ns  
ns  
ns  
ns  
ns  
tVD;DATA  
tVD;DATA  
tVD;ACK  
SCL low to SDA data out valid  
SCL low to SDA data out valid  
SCL low to SDA acknowledge time  
tSTRETCH Clock stretch time (OSR[2:0] = 000b)  
tSP Noise supression time constant on SDA and SCL  
7.9 Switching Characteristics  
at AVDD = 2.35 V to 5 V, DVDD = 1.65 V to 5.5 V, and maximum throughput (unless otherwise noted); minimum and  
maximum values at TA = –40°C to +125°C ; typical values at TA = 25°C.  
PARAMETER  
CONVERSION CYCLE  
TEST CONDITIONS  
MIN  
MAX  
UNIT  
Manual  
Mode and Auto-  
Sequence Mode  
tSTRETCH  
ADC conversion time  
tCONV  
ns  
Autonomous Mode  
600  
192  
ADC comparison time in turbo comparator Turbo Comparator  
mode  
Mode  
RESET AND ALERT  
tPU  
Power-up time for device  
AVDD ≥ 2.35 V  
5
5
ms  
ms  
Delay time; RST bit = 1b to device reset  
complete(1)  
tRST  
ALERT_LOGIC[1:0]  
= 1x  
tALERT_HI  
tALERT_LO  
ALERT high period  
ALERT low period  
50  
50  
150  
150  
ns  
ns  
ALERT_LOGIC[1:0]  
= 1x  
(1) RST bit is automatically reset to 0b after tRST  
.
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7.10 Timing Diagram  
9th clock  
tLOW  
tHIGH  
SCL  
tR  
tSU;DAT  
tF  
tSU;STO  
tSTRETCH  
tHD;STA tHD;DAT  
tSU;STA  
tSP  
SDA  
tF  
tBUF  
tVD;DAT  
tVD;ACK  
P
S
Sr  
P
NOTE: S = Start, Sr = Repeated Start, and P = Stop.  
A. S = start, Sr = repeated start, and P = stop.  
Figure 7-1. I2C Timing Diagram  
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7.11 Typical Characteristics  
at TA = 25°C, AVDD = 5 V, DVDD = 3.3 V, and maximum throughput (unless otherwise noted)  
60000  
45000  
30000  
15000  
0
0.8  
0.4  
0
39581  
25955  
-0.4  
-0.8  
2048  
2049  
0
1024  
2048  
Output Code  
3072  
4095  
Output Code  
C001  
C002  
Standard deviation = 0.49 LSB  
Figure 7-2. DC Input Histogram  
Typical DNL = ±0.2 LSB  
Figure 7-3. Typical DNL  
0.8  
0.4  
0
0.5  
0.3  
Minimum  
Maximum  
0.1  
-0.1  
-0.3  
-0.5  
-0.4  
-0.8  
0
1024  
2048  
Output Code  
3072  
4095  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
C004  
C003  
Typical INL = ±0.5 LSB  
Figure 7-4. Typical INL  
Figure 7-5. DNL vs Temperature  
0.6  
0.3  
0
0.75  
Maximum  
Minimum  
0.5  
0.25  
0
Minimum  
Maximum  
-0.25  
-0.5  
-0.75  
-0.3  
-0.6  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
C005  
C018  
Figure 7-6. INL vs Temperature  
Figure 7-7. DNL vs AVDD  
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7.11 Typical Characteristics (continued)  
at TA = 25°C, AVDD = 5 V, DVDD = 3.3 V, and maximum throughput (unless otherwise noted)  
0.75  
0.5  
Maximum  
Minimum  
0.5  
0.3  
0.25  
0
0.1  
-0.1  
-0.3  
-0.5  
-0.25  
-0.5  
-0.75  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
C019  
C006  
Figure 7-8. INL vs AVDD  
Figure 7-9. Offset Error vs Temperature  
0.75  
0.45  
0.5  
0.3  
0.15  
0.1  
-0.15  
-0.45  
-0.75  
-0.1  
-0.3  
-0.5  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
C007  
C016  
Figure 7-10. Gain Error vs Temperature  
Figure 7-11. Offset Error vs AVDD  
1
0.6  
0.2  
-0.2  
-0.6  
-1  
0
-30  
-60  
-90  
-120  
-150  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
0
16.7  
33.4 50.1  
Frequency (kHz)  
66.8  
83.5  
C017  
C008  
fIN = 2 kHz, SNR = 73.2 dB, THD = 92.3 dB  
Figure 7-12. Gain Error vs AVDD  
Figure 7-13. Typical FFT  
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7.11 Typical Characteristics (continued)  
at TA = 25°C, AVDD = 5 V, DVDD = 3.3 V, and maximum throughput (unless otherwise noted)  
73.6  
73.4  
73.2  
73  
11.85  
11.825  
11.8  
73.5  
73.2  
72.9  
72.6  
72.3  
72  
12  
SINAD  
SNR  
ENOB  
SINAD  
SNR  
ENOB  
11.9  
11.8  
11.7  
11.6  
11.775  
72.8  
11.75  
125  
11.5  
5.5  
-40  
-7  
26 59  
Temperature (°C)  
92  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
C009  
C010  
Figure 7-14. Noise Performance vs Temperature  
Figure 7-15. Noise Performance vs AVDD  
-87  
-88  
-89  
-90  
-91  
-92  
99  
-82  
-84  
-86  
-88  
-90  
94  
92  
90  
88  
THD  
SFDR  
THD  
SFDR  
97.5  
96  
94.5  
93  
91.5  
86  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
C011  
C012  
Figure 7-16. Distortion Performance vs Temperature  
Figure 7-17. Distortion Performance vs AVDD  
145  
132  
129  
126  
123  
120  
117  
140  
135  
130  
125  
120  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
2.5  
3
3.5  
4
AVDD (V)  
4.5  
5
5.5  
C013  
C014  
Figure 7-18. Analog Supply Current vs Temperature  
Figure 7-19. Analog Supply Current vs AVDD  
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7.11 Typical Characteristics (continued)  
at TA = 25°C, AVDD = 5 V, DVDD = 3.3 V, and maximum throughput (unless otherwise noted)  
150  
120  
90  
60  
30  
0
750  
650  
550  
450  
350  
250  
150  
0
30  
60  
90  
Throughput (kSPS)  
120  
150  
180  
C015  
0
500  
1000  
1500  
2000  
Comparison Rate (kSPS)  
2500  
3000  
3500  
Figure 7-20. Analog Supply Current vs Throughput  
C020  
Figure 7-21. Analog Supply Current vs Comparison Rate  
(OSC_SEL = 0) in Turbo Comparator Mode  
40  
34  
28  
22  
16  
10  
750  
740  
730  
720  
710  
700  
690  
0
20  
40 60  
Comparison Rate (kSPS)  
80  
100  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
C021  
C022  
Figure 7-22. Analog Supply Current vs Comparison Rate  
(OSC_SEL = 1) in Turbo Comparator Mode  
Figure 7-23. Analog Supply Current vs Temperature  
(OSC_SEL = 0, CLK_DIV = 0) in Turbo Comparator Mode  
41.5  
40.7  
39.9  
39.1  
38.3  
37.5  
-40  
-7  
26 59  
Temperature (°C)  
92  
125  
C023  
Figure 7-24. Analog Supply Current vs Temperature  
(OSC_SEL = 1, CLK_DIV = 0) in Turbo Comparator Mode  
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8 Detailed Description  
8.1 Overview  
The ADS7138-Q1 is a small, eight-channel, multiplexed, 12-bit, analog-to-digital converter (ADC) with an I2C-  
compatible serial interface. The eight channels of the ADS7138-Q1 can be individually configured as either  
analog inputs, digital inputs, or digital outputs. The device includes a digital window comparator with a dedicated  
ALERT pin that can be used to alert the host when a programmed high or low threshold is crossed on any input  
channel. The device uses an internal oscillator for conversion. The ADC can be used in manual mode for  
reading ADC data over the I 2C interface or in autonomous and turbo comparator modes for monitoring the  
analog inputs without an active I2C interface.  
The device features a programmable averaging filter that outputs a 16-bit result for enhanced resolution.  
The I2C serial interface supports standard-mode, fast-mode, fast-mode plus, and high-speed mode. The device  
also features an 8-bit cyclic redundancy check (CRC) for the serial communication interface.  
8.2 Functional Block Diagram  
DECAP  
AVDD  
High/Low Threshold  
8 x Hysteresis  
DVDD  
AIN0/GPIO0  
AIN1/GPIO1  
AIN2/GPIO2  
AIN3/GPIO3  
AIN4/GPIO4  
AIN5/GPIO5  
AIN6/GPIO6  
AIN7/GPIO7  
ALERT  
Programmable  
Averaging Filter  
ADC  
Digital Window  
Comparator  
MUX  
ADDR  
Sequencer  
Pin CFG  
I2C Interface  
CRC  
SDA  
SCL  
GPO Write  
GPI Read  
RMS Module  
ZCD Module  
GND  
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8.3 Feature Description  
8.3.1 Multiplexer and ADC  
The eight channels of the multiplexer can be independently configured as ADC inputs or general-purpose inputs/  
outputs (GPIOs). As shown in Figure 8-1 every AINx/GPIOx channel has ESD protection diodes to AVDD and  
GND. On power-up or after device reset, all eight multiplexer channels are configured as analog inputs.  
Figure 8-1 shows an equivalent circuit for pins configured as analog inputs. The ADC sampling switch is  
represented by an ideal switch (SW) in series with the resistor (RSW, typically 150 Ω), and the sampling capacitor  
(CSH).  
GPO_VALUE[0]  
GPIO_CFG[0]  
AVDD  
GPI_VALUE[0]  
PIN_CFG[0]  
AIN0 / GPIO0  
RSW  
SW  
MUX  
CSH  
Multiplexer  
AVDD  
ADC  
AIN7 / GPIO7  
PIN_CFG[7]  
GPI_VALUE[7]  
GPIO_CFG[7]  
GPO_VALUE[7]  
Figure 8-1. Analog Inputs, GPIOs, and ADC Connections  
The SW switch is closed to allow the signal on the selected analog input channel to charge the internal sampling  
capacitor during acquisition time. The switch SW is opened to disconnect the sampling capacitor on the ninth  
falling edge of SCL.  
The multiplexer channels can be configured as GPIOs using the PIN_CFG register. The direction of a GPIO  
(either as an input or an output) can be set in the GPIO_CFG register. The logic level on all device channels can  
be read from the GPI_VALUE register. The digital outputs can be configured by writing to the GPO_VALUE  
register. The digital outputs can be configured as either open-drain or push-pull in the GPO_DRIVE_CFG  
register.  
8.3.2 Reference  
The device uses the analog supply voltage (AVDD) as the reference for the analog-to-digital conversion process.  
TI recommends connecting a 1-µF, low-equivalent series resistance (ESR) ceramic decoupling capacitor  
between the AVDD and GND pins.  
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8.3.3 ADC Transfer Function  
The ADC output is in straight binary format. Equation 1 computes the ADC resolution:  
1 LSB = VREF / 2N  
(1)  
where:  
VREF = AVDD  
N = 12  
Figure 8-2 and Table 8-1 detail the transfer characteristics for the device.  
0xFFF  
0x801  
0x800  
0x001  
0x000  
VIN  
(AVDD œ 1 LSB)  
1 LSB  
AVDD/2 (AVDD/2 + 1 LSB)  
Figure 8-2. Ideal Transfer Characteristics  
Table 8-1. Transfer Characteristics  
INPUT VOLTAGE  
CODE  
IDEAL OUTPUT CODE  
≤1 LSB  
Zero  
000  
001  
800  
801  
FFF  
1 LSB to 2 LSBs  
Zero + 1  
(AVDD / 2) to (AVDD / 2) + 1 LSB  
(AVDD / 2) + 1 LSB to (AVDD / 2) + 2 LSB  
≥ AVDD – 1 LSB  
Mid-scale code  
Mid- scale code + 1  
Full-scale code  
8.3.4 ADC Offset Calibration  
The variation in the ADC offset error resulting from changes in temperature or AVDD can be calibrated by setting  
the CAL bit in the GENERAL_CFG register. The CAL bit is reset to 0 after calibration. The host can poll the CAL  
bit to check the ADC offset calibration completion status.  
Multiplexer sequencing must be stopped (SEQ_START = 0b) before initiating offset calibration.  
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8.3.5 I2C Address Selector  
The I2C address for the device is determined by connecting external resistors on the ADDR pin. The device  
address is determined at power-up based on the resistor values. The device retains this address until the next  
power-up event, until the next device reset, or until the device receives a command to program its own address .  
Figure 8-3 shows a connection diagram for the ADDR pin and Table 8-2 lists the resistor values for selecting  
different addresses of the device.  
DECAP Pin  
R1  
ADDR  
R2  
Figure 8-3. External Resistor Connection Diagram for the ADDR Pin  
Table 8-2. I2C Address Selection  
RESISTORS  
ADDRESS  
R1(2)  
0 Ω  
R2(2)  
DNP(1)  
DNP  
001 0111b (17h)  
001 0110b (16h)  
001 0101b (15h)  
001 0100b (14h)  
001 0000b (10h)  
001 0001b (11h)  
001 0010b (12h)  
001 0011b (13h)  
11 kΩ  
33 kΩ  
100 kΩ  
DNP  
DNP  
DNP  
0 Ω or DNP  
11 kΩ  
DNP  
DNP  
33 kΩ  
DNP  
100 kΩ  
(1) DNP = Do not populate.  
(2) Tolerance for R1, R2 ≤ ±5%.  
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8.3.6 Oscillator and Timing Control  
The device uses an internal oscillator for conversions. The host initiates the first conversion and all subsequent  
conversions are generated internally by the device when using the averaging module. However, in the  
autonomous mode of operation, the start of the conversion signal is generated by the device. As described in  
Table 8-3, the sampling rate can be controlled by the OSC_SEL and CLK_DIV register fields when the device  
initiates conversions internally.  
The conversion time of the device, given by tCONV in the Switching Characteristics table, is independent of the  
OSC_SEL and CLK_DIV configuration.  
Table 8-3. Configuring Sampling Rate for Internal Conversion Start Control  
OSC_SEL = 0  
OSC_SEL = 1  
CLK_DIV[3:0]  
SAMPLING FREQUENCY, f  
CYCLE TIME, t  
CYCLE_OSR (µs)  
SAMPLING FREQUENCY, fCYCLE_OSR  
(kSPS)  
CYCLE TIME, t  
CYCLE_OSR (µs)  
CYCLE_OSR (kSPS)  
0000b  
0001b  
0010b  
0011b  
0100b  
0101b  
0110b  
0111b  
1000b  
1001b  
1010b  
1011b  
1100b  
1101b  
1110b  
1111b  
1000  
666.7  
500  
1
1.5  
2
31.25  
20.83  
15.63  
10.42  
7.81  
5.21  
3.91  
2.60  
1.95  
1.3  
32  
48  
64  
333.3  
250  
3
96  
4
128  
192  
256  
384  
512  
768  
1024  
1536  
2048  
3072  
4096  
6144  
166.7  
125  
6
8
83  
12  
16  
24  
32  
48  
64  
96  
128  
192  
62.5  
41.7  
31.3  
20.8  
15.6  
10.4  
7.8  
0.98  
0.65  
0.49  
0.33  
0.24  
0.16  
5.2  
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The comparison time in the turbo comparator mode can be controlled by the OSC_SEL and CLK_DIV register  
fields, as shown in Table 8-4.  
Table 8-4. Configuring Comparison Rate for Turbo Comparator Mode  
OSC_SEL = 0  
OSC_SEL = 1  
CLK_DIV[3:0]  
COMPARISON RATE, f  
COMPARISON (kSPS)  
CYCLE TIME, t  
CYCLE_COMP (µs)  
COMPARISON RATE, fCOMPARISON  
(kSPS)  
CYCLE TIME, t  
CYCLE_COMP (µs)  
0000b  
0001b  
0010b  
0011b  
0100b  
0101b  
0110b  
0111b  
1000b  
1001b  
1010b  
1011b  
1100b  
1101b  
1110b  
1111b  
3200  
2133.3  
1600  
1066.7  
800  
0.3125  
0.46875  
0.625  
0.9375  
1.25  
1.875  
2.5  
100  
66.7  
50  
10  
15  
20  
33.3  
25  
30  
40  
533.3  
400  
16.67  
12.5  
8.33  
6.25  
4.17  
3.13  
2.08  
1.56  
1.04  
0.78  
0.52  
60  
80  
266.7  
200  
3.75  
5
120  
160  
240  
320  
480  
640  
960  
1280  
1920  
133.3  
100  
7.5  
10  
66.7  
50  
15  
20  
33.3  
25  
30  
40  
16.67  
60  
8.3.7 General-Purpose I/Os (GPIOs)  
The eight channels of the ADS7138-Q1 can be independently configured as analog inputs, digital inputs, or  
digital outputs. The device channels, as described in Table 8-5, can be configured as analog inputs or GPIOs  
using the PIN_CFG and GPIO_CFG registers.  
Table 8-5. Configuring Channels as Analog Inputs or GPIOs  
PIN_CFG[7:0]  
GPIO_CFG[7:0]  
GPO_DRIVE_CFG[7:0]  
CHANNEL CONFIGURATION  
0
1
1
1
x
0
1
1
x
x
0
1
Analog input (default)  
Digital input  
Digital output; open-drain driver  
Digital output; push-pull driver  
Digital outputs can be configured to logic 1 or 0 by writing to the GPO_VALUE register. Digital outputs can also  
be updated in response to event flags set by the digital window comparator (see the Triggering Digital Outputs  
With a Digital Window Comparator section for more details). Reading the GPI_VALUE register returns the logic  
level for all channels configured as analog inputs, digital inputs, and digital outputs.  
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8.3.8 Programmable Averaging Filter  
The ADS7138-Q1 features a built-in oversampling (OSR) module that can be used to average several samples.  
The averaging filter can be enabled by programming the OSR[2:0] bits in the OSR_CFG register. The averaging  
filter configuration is common to all analog input channels. As shown in Figure 8-4, the averaging filter module  
output is 16 bits long. Only the first conversion for the selected analog input channel must be initiated by the  
host. Any remaining conversions for the selected averaging factor are generated internally. The time required to  
complete the averaging operation is determined by the sampling speed and number of samples to be averaged;  
see the Oscillator and Timing Control section. The 16-bit result can be read out after the averaging operation  
completes. For more information about programmable averaging filters and performance results, see the  
Resolution-Boosting ADS7138 Using Programmable Averaging Filter appliction report.  
Sample AINX  
Sample AINX  
Sample AINX  
Sample AINX OSR_DONE = 1  
S
7-bit ADDR  
R
A
Bus idle or Poll OSR_DONE bit  
OSR_DONE = 0  
DATA[15:8]  
A
DATA[7:0]  
A
OSR_CFG[2:0] = 2  
Maximum tAVG = N samples x tCYCLE_OSR x 1.06  
Data from host to device  
Data from device to host  
Figure 8-4. Averaging Example  
As shown in Figure 8-4, SCL is stretched by the device after the start of conversions until the averaging  
operation is complete.  
If SCL stretching is not required during averaging, enable the statistics registers by setting STATS_EN to 1b and  
initiate conversions by writing 1b to the CNVST bit. The OSR_DONE bit in the SYSTEM_STATUS register can  
be polled to check the averaging completion status. When using the CNVST bit to initiate conversion, the result  
can be read in the RECENT_CHx_LSB and RECENT_CHx_MSB registers.  
In the autonomous mode of operation, samples from the analog input channels that are enabled in the  
AUTO_SEQ_CH_SEL register are averaged sequentially; see the Autonomous Mode section. The digital  
window comparator compares the top 12 bits of the 16-bit average result with the thresholds.  
Equation 2 provides the LSB value of the 16-bit average result.  
AVDD  
216  
1 LSB =  
(2)  
8.3.9 CRC on Data Interface  
The cyclic redundancy check (CRC) is an error checking code that detects errors in communication between the  
device and the host. The CRC module is optional and can be enabled by the CRC_EN bit in the  
GENERAL_CFG register.  
The CRC data byte is the 8-bit remainder of the bitwise exclusive-OR (XOR) operation of the argument by a  
CRC polynomial. The CRC polynomial is based on the CRC-8-CCITT: X 8 + X 2 + X + 1. The nine binary  
polynomial coefficients are 100000111. The CRC calculation is preset with 0 data values.  
8.3.9.1 Input CRC (From Host To Device)  
The host must compute the appropriate 8-bit CRC corresponding to the 8-bit I2C data (see Figure 8-5). The ADC  
also computes the expected 8-bit CRC corresponding to the 8-bit data received from the host and compares the  
calculated CRC code to the CRC received from the host. The host must not send a CRC byte corresponding to  
the I2C frame containing the device address.  
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S
7-bit Slave Address  
W
A
Byte 1  
A
CRC for Byte 1  
Byte 2  
CRC for Byte 2  
A
A
A
Data from host to device  
Data from device to host  
NOTE: S = Start, Sr = Repeated Start, and P = Stop.  
Figure 8-5. I2C Write With a CRC  
If a CRC error is detected by the device, the command does not execute, and the CRCERR_IN flag is set to 1b.  
The ADC conversion data read and register read, with a valid CRC from the host, are still supported. The error  
condition can be detected, as listed in Table 8-6, by either status flags or by a register read. Further register  
writes to the device are blocked until the CRCERR_IN flag is cleared to 0b. Register write operations, with a  
valid CRC from the host, to the SYSTEM_STATUS and GENERAL_CFG registers are still supported.  
The device can be configured to set all channels to analog inputs on detecting a CRC error by setting the  
CH_RST bit to 1b. This setting ensures channels configured as digital outputs are not driven by the device when  
a CRC error is detected. All channels are reset as per the configuration in the PIN_CFG and GPIO_CFG  
registers when the CRCERR_IN flag is cleared.  
The device can be configured to abort further conversions in autonomous and turbo comparator modes (see the  
Autonomous Mode and Turbo Comparator Mode sections), on detecting a CRC error, by setting  
CONV_ON_ERR = 1b.  
Table 8-6. Configuring Notifications When a CRC Error is Detected  
CRC ERROR NOTIFICATION  
CONFIGURATION  
DESCRIPTION  
ALERT  
ALERT_CRCIN = 1b  
ALERT pin is asserted if a CRC error is detected.  
See the Status Flags section for details.  
Status flags  
APPEND_STATUS = 10b  
Register read  
Read the CRCERR_IN bit to check if a CRC error was detected.  
8.3.9.2 Output CRC (From Device to Host)  
As shown in Figure 8-6, the device sends an 8-bit CRC corresponding to every byte sent by the device over the I  
2C interface.  
S
7-bit Slave Address  
R
A
Byte 1  
A
CRC for Byte 1  
A
Byte 2  
A
CRC for Byte 2  
A
Data from host to device  
Data from device to host  
NOTE: S = Start, Sr = Repeated Start, and P = Stop.  
Figure 8-6. I2C Read With CRC  
8.3.10 Output Data Format  
Figure 8-7 illustrates various I2C frames for reading data.  
Read the ADC conversion result: Two 8-bit I2C packets are required (frame A).  
Read the averaged conversion result: Two 8-bit I2C packets are required (frame B).  
Read data with the channel ID or status flags appended: The 4-bit channel ID or status flags can be  
appended to the 12-bit ADC result by configuring the APPEND_STATUS field in the GENERAL_CFG register.  
The status flags can be used to detect if a CRC error is detected and if an alert condition is detected by the  
digital window comparator. When the channel ID or status flags are appended to the 12-bit ADC data, two I2C  
packets are required (frame C). If the channel ID or status flags are appended to the 16-bit average result,  
three I2C frames are required (frame D).  
When the CRC module is enabled, the device sends an 8-bit CRC for every 8-bit data byte sent over the I2C  
interface; see the Output CRC (From Device to Host) section for more details.  
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Sample A  
Sample A + 1  
S
S
7-bit Slave Address  
7-bit Slave Address  
R
A
D11 D10 D9  
D8  
D7  
D6  
D5  
D4  
A
D3  
D7  
D2  
D6  
D1  
D5  
D0  
D4  
0
0
0
0
A
Frame A : Reading ADC data  
R
A
D15 D14 D13 D12 D11 D10 D9  
D8  
A
D3  
D2  
D1  
D0  
A
Frame B : Reading ADC data with averaging enabled  
4-bit Channel ID  
or Status Flags  
S
S
7-bit Slave Address  
R
R
A
A
D11 D10 D9  
D8  
D7  
D6  
D5  
D4  
A
D3  
D2  
D1  
D0  
A
A
Frame C : Reading ADC data with status flags or channel ID appended  
4-bit Channel ID  
or Status Flags  
7-bit Slave Address  
D15 D14  
D8  
A
D7  
D6  
D0  
A
0
0
0
0
Frame D : Reading ADC data with averaging enabled &  
status flags or channel ID appended  
Clock stretching for conversion time  
Data from host to device  
Data from device to host  
Figure 8-7. Data Frames for Reading Data  
When status flags are enabled, APPEND_STATUS is set to 10b and four bits are appended to the ADC output.  
The device outputs status flags in this order: {1b, 0b, CRCERR_IN, ALERT}. The level transitions on the digital  
interface, resulting from the fixed 1b and 0b in the status flags, can be used to detect if the digital outputs are  
shorted to a fixed voltage in the system. The CRCERR_IN flag reflects the corresponding bit in the  
GENERAL_CFG register. The ALERT flag is the output of the logical OR of the bits in the EVENT_FLAG  
register.  
8.3.10.1 Status Flags  
Status flags can be enabled by setting APPEND_STATUS = 10b. As shown in Figure 8-7, four additional bits are  
appended to the ADC output when status flags are enabled.  
The device outputs status flags in this order: {1b, 0b, CRCERR_IN, ALERT}. The CRCERR_IN flag reflects the  
corresponding bit in the GENERAL_CFG register. The ALERT flag is the output of the logical OR of the bits in  
the EVENT_FLAG register.  
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8.3.11 Digital Window Comparator  
The digital window comparator (DWC) compares the conversion result for an analog input channel with  
programmable high and low thresholds with hysteresis. As shown in Figure 8-8, the DWC sets the  
EVENT_HIGH_FLAG and EVENT_LOW_FLAG registers based on the comparison result sounds better. The  
logical OR of the EVENT_HIGH_FLAG and EVENT_LOW_FLAG registers is available in the EVENT_FLAG  
register. The ALERT pin is asserted when a bit in the EVENT_FLAG register is high and the corresponding bit in  
the ALERT_CH_SEL register is enabled.  
The ALERT pin can be configured as open-drain (default) or push-pull output using the ALERT_DRIVE bit in the  
ALERT_PIN_CFG register.  
EVENT_RGN[7]  
EVENT_RGN[0]  
Digital input CH0  
AL  
High threshold -  
Hysteresis  
12-bit ADC data  
or  
[15:4] Average result  
EVENT_HIGH_FLAG[0]  
EVENT_LOW_FLAG[0]  
MUX  
Programmable  
Averaging Filter  
Event  
Counter  
ADC  
Low threshold +  
Hysteresis  
PIN_CFG[0]  
All registers are specific for  
individual analog input channels  
GPIO_CFG[0]  
Figure 8-8. Digital Window Comparator Block Diagram  
The low-side threshold, high-side threshold, event counter, and hysteresis parameters are independently  
programmable for each input channel. Figure 8-9 shows the events that can be monitored for every analog input  
channel by the window comparator.  
0xFFF  
0xFFF  
High threshold œ 8 x Hysteresis  
Signal above limit  
High threshold œ 8 x Hysteresis  
Low threshold + 8 x Hysteresis  
Signal below limit  
Low threshold + 8 x Hysteresis  
Samples  
0x000  
0xFFF  
0x000  
0xFFF  
Samples  
Signal out of band  
High threshold œ 8 x Hysteresis  
High threshold œ 8 x Hysteresis  
Signal in band  
EVENT_RGN = 0  
Low threshold + 8 x Hysteresis  
Signal out of band  
Samples  
Low threshold + 8 x Hysteresis  
EVENT_RGN = 1  
0x000  
0x000  
Samples  
Figure 8-9. Event Monitoring With the Window Comparator  
To enable the digital window comparator, set the DWC_EN bit in the GENERAL_CFG register. By default,  
hysteresis is 0, the high threshold is 0xFFF, and the low threshold is 0x000. Configure the EVENT_RGN register  
to detect when a signal is within a band defined by the high and low thresholds. In each of the cases shown in  
Figure 8-9, either or both EVENT_HIGH_FLAG and EVENT_LOW_FLAG can be set.  
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The device features a programmable event counter that counts consecutive threshold violations before either  
EVENT_HIGH_FLAG or EVENT_LOW_FLAG are set. An example is shown in Figure 8-10 where the  
EVENT_HIGH_FLAG is not set until eight consecutive conversion results of the corresponding analog input  
channel exceed the threshold configuration. The event count can be set to a higher value to avoid transients in  
the input signal from setting the event flags.  
EVENT_COUNT_CHx = 8  
(waits for 8 counts to set alert)  
2
3
2
1
4
1
5
High Threshold  
6
3
7
8
High Threshold t 8 x Hysteresis  
0
Event counter is reset because the  
high-side-comparator is reset before  
8 samples exceed high threshold.  
High Side Comparator  
(Internal Only Signal)  
EVENT_HIGH_FLAG  
Figure 8-10. False Trigger Avoidance Using the Event Counter  
In order to assert the ALERT pin when the alert flag is set for a particular analog input channel, set the  
corresponding bit in the ALERT_CH_SEL register.  
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8.3.11.1 Interrupts From Digital Inputs  
Rising edge or falling edge events can be detected on channels configured as digital inputs. As described in  
Table 8-7, configure the EVENT_RGN register to select either a rising edge or falling edge event.  
Table 8-7. Configuring Interrupts From Digital Inputs  
PIN_CFG[7:0]  
GPIO_CFG[7:0]  
EVENT_RGN [7:0]  
EVENT DESCRIPTION  
A rising edge on the digital input sets the  
corresponding flag in the EVENT_HIGH_FLAG  
register.  
1
0
0
A falling edge on the digital input sets the  
corresponding flag in the EVENT_LOW_FLAG  
register.  
1
0
1
8.3.11.2 Triggering Digital Outputs With a Digital Window Comparator  
As shown in Figure 8-11, the output value of channels configured as digital outputs can be updated in response  
to one or more flags being set in the EVENT_FLAG register.  
Digital output 7  
Digital output 0  
Select device channels for which corresponding  
bits in EVENT_FLAG should trigger GPO0  
GPO0_EVENT_SEL[7:0]  
trigger  
GPO_UPDATE_ON_EVENT [0]  
Enable the selected EVENT_FLAG bits to trigger  
GPO00  
Default  
0
1
GPO_VALUE [0]  
GPO_VALUE_ON_EVENT [0]  
Output value when one of the selected  
events is asserted  
Figure 8-11. Block Diagram of the Digital Output Logic  
The following procedure enables updating the output value of a digital output in response to event flags:  
1. Configure the device channels as either analog inputs (default), digital inputs, or digital outputs.  
2. Configure the digital outputs as either open-drain (default) or push-pull outputs.  
3. Configure the digital window comparator for the input channels. The digital window comparator updates the  
flags in the EVENT_FLAG register corresponding to individual channels. See the Digital Window Comparator  
section for more details.  
4. Select the bits corresponding to the input channels that are to be enabled for triggering the digital output in  
the GPOx_EVENT_SEL register (where x is the digital output channel number).  
5. The default output value of the digital output, when no event flag is set, is configured in the GPO_VALUE  
register. The output value of the digital output, when event flags are set, is configured in the  
GPO_VALUE_ON_EVENT register.  
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6. Configure the GPO_UPDATE_ON_EVENT register to enable the logic to update the selected digital output in  
response to event flags.  
The configuration in GPO_VALUE sets the output value of a dgital output when either no event flags are set or  
when event flags are reset in the EVENT_FLAG register corresponding to channels selected in the  
GPOx_EVENT_SEL register.  
8.3.12 Minimum, Maximum, and Latest Data Registers  
The ADS7138-Q1 can record the minimum, maximum, and latest code (statistics registers) for every analog  
input channel. To enable or re-enable recording statistics, set the STATS_EN bit in the GENERAL_CFG register.  
Writing 1 to the STATS_EN bit reinitializes the statistics module. Previous values can be read from the statistics  
registers until a new conversion result is available. Set STATS_EN = 0b to prevent any updates to this block of  
registers before reading the statistics registers.  
8.3.13 I2C Protocol Features  
8.3.13.1 General Call  
On receiving a general call (00h), the device provides an acknowledge (ACK).  
8.3.13.2 General Call With Software Reset  
On receiving a general call (00h) followed by a software reset (06h), the device resets itself.  
8.3.13.3 General Call With a Software Write to the Programmable Part of the Slave Address  
On receiving a general call (00h) followed by 04h, the device reevaluates its own I2C address configured by the  
ADDR pin. During this operation, the device does not respond to other I2C commands except the general-call  
command.  
8.3.13.4 Configuring the Device for High-Speed I2C Mode  
The device can be configured in high-speed I2C mode by providing an I2C frame with one of these codes: 0x09,  
0x0B, 0x0D, or 0x0F.  
After receiving one of these codes, the device sets the I2C_SPEED bit in the SYSTEM_STATUS register and  
remains in high-speed I2C mode until a STOP condition is received in an I2C frame.  
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8.4 Device Functional Modes  
Table 8-8 lists the functional modes supported by the ADS7138-Q1. The device powers up in manual mode (see  
the Manual Mode section) and can be configured into any mode listed in Table 8-8 by writing the configuration  
registers for the desired mode.  
Table 8-8. Functional Modes  
FUNCTIONAL MODE CONVERSION CONTROL  
MUX CONTROL  
CONV_MODE[1:0]  
SEQ_MODE[1:0]  
Register write to  
Manual  
9th falling edge of SCL (ACK)  
00b  
00b  
MANUAL_CHID  
9th falling edge of SCL (ACK) Channel sequencer  
Auto-sequence  
Autonomous  
00b  
01b  
10b  
01b  
01b  
01b  
Internal to the device  
Internal to the device  
Channel sequencer  
Channel sequencer  
Turbo comparator  
8.4.1 Device Power-Up and Reset  
On power-up, the device calculates the address from the resistors connected on the ADDR pin and the BOR bit  
is set, thus indicating a power-cycle or reset event.  
The device can be reset by an I2C general call (00h) followed by a software reset (06h), by setting the RST bit,  
or by recycling the power on the AVDD pin.  
8.4.2 Manual Mode  
Manual mode allows the external host processor to directly select the analog input channel. Figure 8-12 lists the  
steps for operating the device in manual mode.  
Idle  
SEQ_MODE = 0b  
CONV_MODE = 0b  
Configure channels as AIN/GPIO using PIN_CFG  
Calibrate offset error (CAL = 1b)  
Select Manual mode  
(CONV_MODE = 00b, SEQ_MODE = 00b)  
Configure desired Channel ID in MANUAL_CHID field  
Host provides Conversion Start Frame on I2C Bus  
Host provides Conversion Read Frame on I2C Bus  
No  
Yes  
Same  
Channel ID?  
Manual mode with channel selection using register write  
Figure 8-12. Device Operation in Manual Mode  
Provide an I2C start or restart frame to initiate a conversion, as illustrated in the conversion start frame of Figure  
8-13, after configuring the device registers. ADC data can be read in subsequent I2C frames. The number of I2C  
frames required to read conversion data depends on the output data frame size; see the Output Data Format  
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section for more details. A new conversion is initiated on the ninth falling edge of SCL (ACK bit) when the last  
byte of output data is read.  
Sample A + 1  
Sample A  
S
7-bit Slave Address  
R
A
8 bit I2C frame  
A
8 bit I2C frame  
A
8 bit I2C frame  
A
8 bit I2C frame  
A
Clock stretching for conversion time  
Clock stretching for conversion time  
Data from host to device  
Data from device to host  
Figure 8-13. Starting a Conversion and Reading Data in Manual Mode  
8.4.3 Auto-Sequence Mode  
In auto-sequence mode, the internal channel sequencer switches the multiplexer to the next analog input  
channel after every conversion. The desired analog input channels can be configured for sequencing in the  
AUTO_SEQ_CH_SEL register. To enable the channel sequencer, set SEQ_START to 1b. After every  
conversion, the channel sequencer switches the multiplexer to the next analog input in ascending order. To stop  
the channel sequencer from selecting channels, set SEQ_START to 0b. Figure 8-14 lists the conversion start  
and read frames for auto-sequence mode.  
Idle  
SEQ_MODE = 0b  
CONV_MODE = 0b  
Configure channels as AIN/GPIO using PIN_CFG  
Calibrate offset error (CAL = 1b)  
Enable analog inputs for sequencing (AUTO_SEQ_CH_SEL)  
Select Auto-sequence mode (SEQ_MODE = 01b)  
(optional) Configure alert conditions  
(optional) Append Channel ID to data using APPEND_STATUS  
Enable channel sequencing SEQ_START = 1b  
Host provides Conversion Start Frame on I2C Bus  
Host provides Conversion Read Frame on I2C Bus  
Device selects next channel according to AUTO_SEQ_CH_SEL  
Yes  
Continue?  
No  
Disable channel sequencing SEQ_START = 0b  
Idle  
Figure 8-14. Device Operation in Auto-Sequence Mode  
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8.4.4 Autonomous Mode  
In autonomous mode, the device can be programmed to monitor the voltage applied on the analog input pins of  
the device and generate a signal on the ALERT pin when the programmable high or low threshold values are  
crossed. In this mode, the device generates the start of conversion using the internal oscillator. The first start of  
conversion must be provided by the host and the device then generates the subsequent start of conversions.  
Figure 8-15 shows the steps for configuring the operation mode to autonomous mode. Abort the ongoing  
sequence by setting SEQ_START to 0b before changing the functional mode or device configuration.  
Idle  
SEQ_MODE = 0b  
CONV_MODE = 0b  
Configure channels as AIN/GPIO using PIN_CFG  
Calibrate offset error (CAL = 1b)  
Channel  
selection  
Enable analog inputs for sequencing (AUTO_SEQ_CH_SEL)  
Select Auto-sequence mode (SEQ_MODE = 01b)  
Configure alert condition using HIGH_TH_CHx,  
LOW_TH_CHx,EVENT_COUNT_CHx, HYSTERESIS_CHx, and  
EVENT_REGION_CHx fields  
Threshold & Alert  
configuration  
Enable analog inputs to trigger ALERT pinusing ALERT_CH_SEL  
Configuration  
Configure ALERT pin using ALERT_DRIVE and ALERT_LOGIC fields  
Configure sampling rate of analog inputsusing OSC_SEL and CLK_DIV  
Set mode to autonomous monitoring (CONV_MODE = 01b)  
Sampling rate  
configuration  
(optional) Enable averaging and min/max recording (OSR[2:0] and STATS_EN)  
Enable threshold comparison (DWC_EN = 1b)  
Enable autonomous monitoring (SEQ_START = 1b)  
Active Operation  
(Digital  
communication  
No  
(optional) read conversion results in  
MIN_VALUE_CHx, MAX_VALUE_CHx, and  
LAST_VALUE_CHx registers  
interface can be idle)  
ALERT?  
Yes  
Stop autonomous monitoring (SEQ_START = 0b)  
Disable threshold comparison (DWC_EN = 0b)  
ALERT Detected  
Read alert flags œ EVENT_FLAG, EVENT_HIGH_FLAG, EVENT_LOW_FLAG  
Clear alert flags œ EVENT_HIGH_FLAG, EVENT_LOW_FLAG  
Figure 8-15. Configuring the Device in Autonomous Mode  
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8.4.5 Turbo Comparator Mode  
Turbo comparator mode allows fast comparison with high and low thresholds using the digital window  
comparator. ADC output data are not available in this mode.  
Figure 8-16 lists the comparison start and read frames for turbo comparator mode. The desired analog input  
channels can be configured for sequencing in the AUTO_SEQ_CH_SEL register. To enable the channel  
sequencer, set SEQ_START to 1b. After every comparison, the channel sequencer switches the multiplexer to  
the next analog input in ascending order. To stop the channel sequencer from selecting channels, set  
SEQ_START to 0b. See the Oscillator and Timing Control section for more details on configuring the speed in  
turbo comparator mode.  
Abort the ongoing sequence by setting SEQ_START to 0b before changing the functional mode or device  
configuration.  
Idle  
SEQ_MODE = 0b  
CONV_MODE = 0b  
Configure channels as AIN/GPIO using PIN_CFG  
Calibrate offset error (CAL = 1b)  
Channel  
selection  
Enable analog inputs for sequencing (AUTO_SEQ_CH_SEL)  
Select auto-sequence mode (SEQ_MODE = 01b)  
Configure alert condition using HIGH_TH_CHx,  
LOW_TH_CHx,EVENT_COUNT_CHx, HYSTERESIS_CHx, and  
EVENT_REGION_CHx fields  
Threshold & Alert  
configuration  
Enable analog inputs to trigger ALERT pinusing ALERT_CH_SEL  
Configuration  
Configure ALERT pin using ALERT_DRIVE and ALERT_LOGIC fields  
Configure sampling rate of analog inputsusing OSC_SEL and CLK_DIV  
Select turbo comparator mode (CONV_MODE = 10b)  
Sampling rate  
configuration  
Enable threshold comparison (DWC_EN = 1b)  
Start turbo comparator mode (SEQ_START = 1b)  
Active Operation  
(Digital  
communication  
interface can be idle)  
No  
ALERT?  
Yes  
Stop turbo comparator mode (SEQ_START = 0b)  
Disable threshold comparison (DWC_EN = 0b)  
ALERT Detected  
Read alert flags œ EVENT_FLAG, EVENT_HIGH_FLAG, EVENT_LOW_FLAG  
Clear alert flags œ EVENT_HIGH_FLAG, EVENT_LOW_FLAG  
Figure 8-16. Device Operation in Turbo Comparator Mode  
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8.5 Programming  
Table 8-9 provides the acronyms for different conditions in an I2C frame. Table 8-10 lists the various command  
opcodes.  
Table 8-9. I2C Frame Acronyms  
SYMBOL  
DESCRIPTION  
Start condition for the I2C frame  
Restart condition for the I2C frame  
Stop condition for the I2C frame  
ACK (low)  
S
Sr  
P
A
N
R
W
NACK (high)  
Read bit (high)  
Write bit (low)  
Table 8-10. Opcodes for Commands  
OPCODE  
0001 0000b  
0000 1000b  
0001 1000b  
0010 0000b  
0011 0000b  
0010 1000b  
COMMAND DESCRIPTION  
Single register read  
Single register write  
Set bit  
Clear bit  
Reading a continuous block of registers  
Writing a continuous block of registers  
8.5.1 Register Read  
The I2C master can either read a single register or a continuous block registers from the device, as described in  
the Single Register Read and Reading a Continuous Block of Registers sections.  
8.5.1.1 Single Register Read  
To read a single register from the device, the I2C master must provide an I2C command with three frames to set  
the register address for reading data. The opcodes for commands supported by the device are listed in Table  
8-10. After an I2C command is provided, the I2C master must provide another I2C frame (as shown in Figure  
8-17) containing the device address and the read bit. The device provides the register data in the next I2C frame.  
The device provides the same register data even if the host provides more I2C frames. To end the register read  
command, the master must provide a STOP or a RESTART condition in the I2C frame.  
Register  
Address  
S
7-bit Slave Address  
W
A
0001 0000b  
A
A
P/Sr  
S
7-bit Slave Address  
R
A
Register Data  
A
P/Sr  
Data from host to device  
Data from device to host  
S = start, Sr = repeated start, and P = stop.  
Figure 8-17. Single Register Read  
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8.5.1.2 Reading a Continuous Block of Registers  
To read a continuous block of registers, the I 2C master must provide an I 2C command to set the register  
address. The register address is the address of the first register in the block that must be read. After this  
command is provided, the I2C master must provide another I2C frame, as shown in Figure 8-18, containing the  
device address and the read bit. After this frame, the device provides the register data. The device provides data  
for the next register when more clocks are provided. When data are read from addresses that do not exist in the  
register map of the device, the device returns zeros. If the device does not have any further registers to provide  
data on, the device provide zeros. To end the register read command, the master must provide a STOP or a  
RESTART condition in the I2C frame.  
1st Reg Address  
in the Block  
S
7-bit Slave Address  
W
A
0011 0000b  
A
A
P/Sr  
S
7-bit Slave Address  
R
A
Register Data  
A
P/Sr  
Data from host to device  
Data from device to host  
S = start, Sr = repeated start, and P = stop.  
Figure 8-18. Reading a Continuous Block of Registers  
8.5.2 Writing Registers  
The I2C master can either write a single register or a continuous block of registers to the device, set a few bits in  
a register, or clear a few bits in a register.  
8.5.2.1 Single Register Write  
To write a single register from the device, as shown in Figure 8-19, the I2C master must provide an I2C command  
with four frames. The register address is the address of the register that must be written and the register data is  
the value that must be written. Table 8-10 lists the opcodes for different commands. To end the register write  
command, the master must provide a STOP or a RESTART condition in the I2C frame.  
Register  
Address  
S
7-bit Slave Address  
W
A
0000 1000b  
A
A
Register Data  
A
P/Sr  
Data from host to device  
Data from device to host  
S = start, Sr = repeated start, and P = stop.  
Figure 8-19. Writing a Single Register  
8.5.2.2 Set Bit  
The I2C master must provide an I2C command with four frames, as shown in Figure 8-19, to set bits in a register  
without changing the other bits. The register address is the address of the register that the bits must set and the  
register data is the value representing the bits that must be set. Bits with a value of 1 in the register data are set  
and bits with a value of 0 in the register data are not changed. Table 8-10 lists the opcodes for different  
commands. To end this command, the master must provide a STOP or RESTART condition in the I2C frame.  
8.5.2.3 Clear Bit  
The I2C master must provide an I2C command with four frames, as shown in Figure 8-19, to clear bits in a  
register without changing the other bits. The register address is the address of the register that the bits must  
clear and the register data is the value representing the bits that must be cleared. Bits with a value of 1 in the  
register data are cleared and bits with a value of 0 in the register data are not changed. Table 8-10 lists the  
opcodes for different commands. To end this command, the master must provide a STOP or a RESTART  
condition in the I2C frame.  
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8.5.2.4 Writing a Continuous Block of Registers  
The I2C master must provide an I2C command, as shown in Figure 8-20, to write a continuous block of registers.  
The register address is the address of the first register in the block that must be written. The I2C master must  
provide data for registers in subsequent I2C frames in an ascending order of register addresses. Writing data to  
addresses that do not exist in the register map of the device have no effect. Table 8-10 lists the opcodes for  
different commands. If the data provided by the I2C master exceeds the address space of the device, the device  
ignores the data beyond the address space. To end the register write command, the master must provide a  
STOP or a RESTART condition in the I2C frame.  
1st Reg Address  
in the block  
S
7-bit Slave Address  
W
A
0010 1000b  
A
A
Register Data  
A
P/Sr  
Data from host to device  
Data from device to host  
S = start, Sr = repeated start, and P = stop.  
Figure 8-20. Writing a Continuous Block of Registers  
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8.6 ADS7138-Q1 Registers  
Table 8-11 lists the memory-mapped registers for the ADS7138-Q1 registers. All register offset addresses not  
listed in Table 8-11 should be considered as reserved locations and the register contents should not be modified.  
Table 8-11. ADS7138-Q1 Registers  
Address  
0x0  
Acronym  
Register Name  
Section  
SYSTEM_STATUS  
GENERAL_CFG  
DATA_CFG  
Section 8.6.1  
Section 8.6.2  
Section 8.6.3  
Section 8.6.4  
Section 8.6.5  
Section 8.6.6  
Section 8.6.7  
Section 8.6.8  
Section 8.6.9  
Section 8.6.10  
Section 8.6.11  
Section 8.6.12  
Section 8.6.13  
Section 8.6.14  
Section 8.6.15  
Section 8.6.16  
Section 8.6.17  
Section 8.6.18  
Section 8.6.19  
Section 8.6.20  
Section 8.6.21  
Section 8.6.22  
Section 8.6.23  
Section 8.6.24  
Section 8.6.25  
Section 8.6.26  
Section 8.6.27  
Section 8.6.28  
Section 8.6.29  
Section 8.6.30  
Section 8.6.31  
Section 8.6.32  
Section 8.6.33  
Section 8.6.34  
Section 8.6.35  
Section 8.6.36  
Section 8.6.37  
Section 8.6.38  
Section 8.6.39  
Section 8.6.40  
Section 8.6.41  
0x1  
0x2  
0x3  
OSR_CFG  
0x4  
OPMODE_CFG  
PIN_CFG  
0x5  
0x7  
GPIO_CFG  
0x9  
GPO_DRIVE_CFG  
GPO_VALUE  
0xB  
0xD  
GPI_VALUE  
0x10  
0x11  
0x12  
0x14  
0x16  
0x17  
0x18  
0x1A  
0x1C  
0x1E  
0x20  
0x21  
0x22  
0x23  
0x24  
0x25  
0x26  
0x27  
0x28  
0x29  
0x2A  
0x2B  
0x2C  
0x2D  
0x2E  
0x2F  
0x30  
0x31  
0x32  
0x33  
0x34  
SEQUENCE_CFG  
MANUAL_CH_SEL  
AUTO_SEQ_CH_SEL  
ALERT_CH_SEL  
ALERT_FUNC_SEL  
ALERT_PIN_CFG  
EVENT_FLAG  
EVENT_HIGH_FLAG  
EVENT_LOW_FLAG  
EVENT_RGN  
HYSTERESIS_CH0  
HIGH_TH_CH0  
EVENT_COUNT_CH0  
LOW_TH_CH0  
HYSTERESIS_CH1  
HIGH_TH_CH1  
EVENT_COUNT_CH1  
LOW_TH_CH1  
HYSTERESIS_CH2  
HIGH_TH_CH2  
EVENT_COUNT_CH2  
LOW_TH_CH2  
HYSTERESIS_CH3  
HIGH_TH_CH3  
EVENT_COUNT_CH3  
LOW_TH_CH3  
HYSTERESIS_CH4  
HIGH_TH_CH4  
EVENT_COUNT_CH4  
LOW_TH_CH4  
HYSTERESIS_CH5  
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Table 8-11. ADS7138-Q1 Registers (continued)  
Address  
0x35  
0x36  
0x37  
0x38  
0x39  
0x3A  
0x3B  
0x3C  
0x3D  
0x3E  
0x3F  
0x60  
0x61  
0x62  
0x63  
0x64  
0x65  
0x66  
0x67  
0x68  
0x69  
0x6A  
0x6B  
0x6C  
0x6D  
0x6E  
0x6F  
0x80  
0x81  
0x82  
0x83  
0x84  
0x85  
0x86  
0x87  
0x88  
0x89  
0x8A  
0x8B  
0x8C  
0x8D  
0x8E  
0x8F  
0xA0  
0xA1  
Acronym  
Register Name  
Section  
HIGH_TH_CH5  
EVENT_COUNT_CH5  
LOW_TH_CH5  
HYSTERESIS_CH6  
HIGH_TH_CH6  
EVENT_COUNT_CH6  
LOW_TH_CH6  
HYSTERESIS_CH7  
HIGH_TH_CH7  
EVENT_COUNT_CH7  
LOW_TH_CH7  
MAX_CH0_LSB  
MAX_CH0_MSB  
MAX_CH1_LSB  
MAX_CH1_MSB  
MAX_CH2_LSB  
MAX_CH2_MSB  
MAX_CH3_LSB  
MAX_CH3_MSB  
MAX_CH4_LSB  
MAX_CH4_MSB  
MAX_CH5_LSB  
MAX_CH5_MSB  
MAX_CH6_LSB  
MAX_CH6_MSB  
MAX_CH7_LSB  
MAX_CH7_MSB  
MIN_CH0_LSB  
MIN_CH0_MSB  
MIN_CH1_LSB  
MIN_CH1_MSB  
MIN_CH2_LSB  
MIN_CH2_MSB  
MIN_CH3_LSB  
MIN_CH3_MSB  
MIN_CH4_LSB  
MIN_CH4_MSB  
MIN_CH5_LSB  
MIN_CH5_MSB  
MIN_CH6_LSB  
MIN_CH6_MSB  
MIN_CH7_LSB  
MIN_CH7_MSB  
RECENT_CH0_LSB  
RECENT_CH0_MSB  
Section 8.6.42  
Section 8.6.43  
Section 8.6.44  
Section 8.6.45  
Section 8.6.46  
Section 8.6.47  
Section 8.6.48  
Section 8.6.49  
Section 8.6.50  
Section 8.6.51  
Section 8.6.52  
Section 8.6.53  
Section 8.6.54  
Section 8.6.55  
Section 8.6.56  
Section 8.6.57  
Section 8.6.58  
Section 8.6.59  
Section 8.6.60  
Section 8.6.61  
Section 8.6.62  
Section 8.6.63  
Section 8.6.64  
Section 8.6.65  
Section 8.6.66  
Section 8.6.67  
Section 8.6.68  
Section 8.6.69  
Section 8.6.70  
Section 8.6.71  
Section 8.6.72  
Section 8.6.73  
Section 8.6.74  
Section 8.6.75  
Section 8.6.76  
Section 8.6.77  
Section 8.6.78  
Section 8.6.79  
Section 8.6.80  
Section 8.6.81  
Section 8.6.82  
Section 8.6.83  
Section 8.6.84  
Section 8.6.85  
Section 8.6.86  
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Table 8-11. ADS7138-Q1 Registers (continued)  
Address  
0xA2  
0xA3  
0xA4  
0xA5  
0xA6  
0xA7  
0xA8  
0xA9  
0xAA  
0xAB  
0xAC  
0xAD  
0xAE  
0xAF  
0xC3  
0xC5  
0xC7  
0xC9  
0xCB  
0xCD  
0xCF  
0xD1  
0xE9  
0xEB  
Acronym  
Register Name  
Section  
RECENT_CH1_LSB  
RECENT_CH1_MSB  
RECENT_CH2_LSB  
RECENT_CH2_MSB  
RECENT_CH3_LSB  
RECENT_CH3_MSB  
RECENT_CH4_LSB  
RECENT_CH4_MSB  
RECENT_CH5_LSB  
RECENT_CH5_MSB  
RECENT_CH6_LSB  
RECENT_CH6_MSB  
RECENT_CH7_LSB  
RECENT_CH7_MSB  
GPO0_TRIG_EVENT_SEL  
GPO1_TRIG_EVENT_SEL  
GPO2_TRIG_EVENT_SEL  
GPO3_TRIG_EVENT_SEL  
GPO4_TRIG_EVENT_SEL  
GPO5_TRIG_EVENT_SEL  
GPO6_TRIG_EVENT_SEL  
GPO7_TRIG_EVENT_SEL  
GPO_TRIGGER_CFG  
GPO_VALUE_TRIG  
Section 8.6.87  
Section 8.6.88  
Section 8.6.89  
Section 8.6.90  
Section 8.6.91  
Section 8.6.92  
Section 8.6.93  
Section 8.6.94  
Section 8.6.95  
Section 8.6.96  
Section 8.6.97  
Section 8.6.98  
Section 8.6.99  
Section 8.6.100  
Section 8.6.101  
Section 8.6.102  
Section 8.6.103  
Section 8.6.104  
Section 8.6.105  
Section 8.6.106  
Section 8.6.107  
Section 8.6.108  
Section 8.6.109  
Section 8.6.110  
Complex bit access types are encoded to fit into small table cells. Table 8-12 shows the codes that are used for  
access types in this section.  
Table 8-12. ADS7138-Q1 Access Type Codes  
Access Type  
Read Type  
R
Code  
Description  
R
Read  
Write Type  
W
W
Write  
Reset or Default Value  
-n  
Value after reset or the default  
value  
Register Array Variables  
i,j,k,l,m,n  
When these variables are used in  
a register name, an offset, or an  
address, they refer to the value of  
a register array where the register  
is part of a group of repeating  
registers. The register groups  
form a hierarchical structure and  
the array is represented with a  
formula.  
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Table 8-12. ADS7138-Q1 Access Type Codes  
(continued)  
Access Type  
Code  
Description  
y
When this variable is used in a  
register name, an offset, or an  
address it refers to the value of a  
register array.  
8.6.1 SYSTEM_STATUS Register (Address = 0x0) [Reset = 0x81]  
SYSTEM_STATUS is shown in Figure 8-17 and described in Table 8-13.  
Return to the Table 8-11.  
Figure 8-17. SYSTEM_STATUS Register  
7
6
5
4
3
2
1
0
RSVD  
SEQ_STATUS  
I2C_SPEED  
RESERVED  
OSR_DONE  
CRC_ERR_FU CRC_ERR_IN  
SE  
BOR  
R-1b  
R-0b  
R-0b  
R-0b  
R/W-0b  
R-0b  
R/W-0b  
R/W-1b  
Table 8-13. SYSTEM_STATUS Register Field Descriptions  
Bit  
7
Field  
Type  
Reset  
Description  
RSVD  
R
1b  
Reads return 1b.  
6
SEQ_STATUS  
R
0b  
Status of the channel sequencer.  
0b = Sequence stopped  
1b = Sequence in progress  
5
I2C_SPEED  
R
0b  
I2C high-speed status.  
0b = I2C bus is not in high-speed mode.  
1b = I2C bus is in high-speed mode.  
4
3
RESERVED  
OSR_DONE  
R
0b  
0b  
Reserved Bit  
R/W  
Averaging status. Clear this bit by writing 1b to this bit.  
0b = Averaging in progress or not started; average result is not  
ready.  
1b = Averaging complete; average result is ready.  
2
1
CRC_ERR_FUSE  
CRC_ERR_IN  
R
0b  
0b  
Device power-up configuration CRC check status. To re-evaluate this  
bit, software reset the device or power cycle AVDD.  
0b = No problems detected in power-up configuration.  
1b = Device configuration not loaded correctly.  
R/W  
Status of CRC check on incoming data. Write 1b to clear this error  
flag.  
0b = No CRC error.  
1b = CRC error detected. All register writes, except to addresses  
0x00 and 0x01, are blocked.  
0
BOR  
R/W  
1b  
Brown out reset indicator. This bit is set if brown out condition occurs  
or device is power cycled. Write 1b to this bit to clear the flag.  
0b = No brown out condition detected from last time this bit was  
cleared.  
1b = Brown out condition detected or device power cycled.  
8.6.2 GENERAL_CFG Register (Address = 0x1) [Reset = 0x0]  
GENERAL_CFG is shown in Figure 8-18 and described in Table 8-14.  
Return to the Table 8-11.  
Figure 8-18. GENERAL_CFG Register  
7
6
5
4
3
2
1
0
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Figure 8-18. GENERAL_CFG Register (continued)  
RESERVED  
R-0b  
CRC_EN  
R/W-0b  
STATS_EN  
DWC_EN  
CNVST  
CH_RST  
CAL  
RST  
R/W-0b  
R/W-0b  
W-0b  
R/W-0b  
R/W-0b  
W-0b  
Table 8-14. GENERAL_CFG Register Field Descriptions  
Bit  
7
Field  
RESERVED  
Type  
Reset  
Description  
R
0b  
Reserved Bit  
6
CRC_EN  
R/W  
0b  
Enable or disable the CRC on device interface.  
0b = CRC module disabled.  
1b = CRC appended to data output. CRC check is enabled on  
incoming data.  
5
STATS_EN  
R/W  
0b  
Enable or disable the statistics module to update minimu, maximum,  
and latest output code registers.  
0b = Statistics registers are not updated.  
1b = Clear statistics registers and conitnue updating with new  
conversion results.  
4
3
DWC_EN  
CNVST  
R/W  
W
0b  
0b  
Enable or disable the digital window comparator.  
0b = Reset or disable the digital window comparator.  
1b = Enable the digital window comparator.  
Control start conversion on selected analog input. Readback of this  
bit returns 0b.  
0b = Normal operation; conversions starts on the 9th falling edge of I  
2C frame. Device stretches SCL until end of conversion or  
completion of averaging.  
1b = Initiate start of conversion. Device does not stretch SCL until  
end of conversion or completion of averaging.  
2
1
0
CH_RST  
CAL  
R/W  
R/W  
W
0b  
0b  
0b  
Force all channels to be analog inputs.  
0b = Normal operation.  
1b = All channels are configured as analog inputs irrespective of  
configuration in other registers.  
Calibrate ADC offset.  
0b = Normal operation.  
1b = ADC offset is calibrated. After calibration is complete, this bit is  
set to 0b by the device.  
RST  
Software reset all registers to default values.  
0b = Normal operation.  
1b = Device is reset. After reset is complete, this bit is set to 0b and  
BOR bit is set to 1b by the device.  
8.6.3 DATA_CFG Register (Address = 0x2) [Reset = 0x0]  
DATA_CFG is shown in Figure 8-19 and described in Table 8-15.  
Return to the Table 8-11.  
Figure 8-19. DATA_CFG Register  
7
6
5
4
3
2
1
0
FIX_PAT  
R/W-0b  
RESERVED  
R-0b  
APPEND_STATUS[1:0]  
R/W-0b  
RESERVED  
R-0b  
Table 8-15. DATA_CFG Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7
FIX_PAT  
R/W  
0b  
Device will output fixed data bits, which can be helpful for debugging  
communication with the device.  
0b = Normal operation.  
1b = Device outputs fixed code 0xA5A repeatitively when reading  
data.  
6
RESERVED  
R
0b  
Reserved Bit  
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Table 8-15. DATA_CFG Register Field Descriptions (continued)  
Bit  
Field  
Type  
Reset  
Description  
5-4  
APPEND_STATUS[1:0]  
R/W  
0b  
Append 4-bit channel ID or status flags to output data.  
0b = Channel ID and status flags are not appended to ADC data.  
1b = 4-bit channel ID is appended to ADC data.  
10b = 4-bit status flags are appended to ADC data.  
11b = Reserved.  
3-0  
RESERVED  
R
0b  
Reserved Bit  
8.6.4 OSR_CFG Register (Address = 0x3) [Reset = 0x0]  
OSR_CFG is shown in Figure 8-20 and described in Table 8-16.  
Return to the Table 8-11.  
Figure 8-20. OSR_CFG Register  
7
6
5
4
3
2
1
0
RESERVED  
R-0b  
OSR[2:0]  
R/W-0b  
Table 8-16. OSR_CFG Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-3  
2-0  
RESERVED  
OSR[2:0]  
R
0b  
Reserved Bit  
R/W  
0b  
Selects the oversampling ratio for ADC conversion result.  
0b = No averaging  
1b = 2 samples  
10b = 4 samples  
11b = 8 samples  
100b = 16 samples  
101b = 32 samples  
110b = 64 samples  
111b = 128 samples  
8.6.5 OPMODE_CFG Register (Address = 0x4) [Reset = 0x0]  
OPMODE_CFG is shown in Figure 8-21 and described in Table 8-17.  
Return to the Table 8-11.  
Figure 8-21. OPMODE_CFG Register  
7
6
5
4
3
2
1
0
CONV_ON_ER  
R
CONV_MODE[1:0]  
OSC_SEL  
CLK_DIV[3:0]  
R/W-0b  
R/W-0b  
R/W-0b  
R/W-0b  
Table 8-17. OPMODE_CFG Register Field Descriptions  
Bit  
Field  
CONV_ON_ERR  
Type  
Reset  
Description  
7
R/W  
0b  
Control continuation of autonomous and turbo comparator modes if  
CRC error is detected on communication interface.  
0b = If CRC error is detected, device continues channel sequencing  
and pin configuration is retained. See the CRC_ERR_IN bit for more  
details.  
1b = If CRC error is detected, device changes all channels to analog  
inputs and channel sequencing is paused until CRC_ERR_IN = 1b.  
After clearing CRC_ERR_IN flag, device resumes channel  
sequencing and pin confguration is restored.  
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Table 8-17. OPMODE_CFG Register Field Descriptions (continued)  
Bit  
Field  
Type  
Reset  
Description  
6-5  
CONV_MODE[1:0]  
R/W  
0b  
These bits set the mode of conversion of the ADC.  
0b = Manual mode; conversions are initiated by host.  
1b = Autonomous mode; conversions are initiated by internal state  
machine.  
10b = Turbo mode; comparisons are initiated by internal state  
machine.  
4
OSC_SEL  
R/W  
R/W  
0b  
0b  
Selects the oscillator for internal timing generation.  
0b = High-speed oscillator.  
1b = Low-power oscillator.  
3-0  
CLK_DIV[3:0]  
Sampling speed control. See the section on oscillator and timing  
control for details.  
8.6.6 PIN_CFG Register (Address = 0x5) [Reset = 0x0]  
PIN_CFG is shown in Figure 8-22 and described in Table 8-18.  
Return to the Table 8-11.  
Figure 8-22. PIN_CFG Register  
7
6
5
4
3
2
1
0
PIN_CFG[7:0]  
R/W-0b  
Table 8-18. PIN_CFG Register Field Descriptions  
Bit  
7-0  
Field  
PIN_CFG[7:0]  
Type  
Reset  
Description  
R/W  
0b  
Configure device channels AIN/GPIO[7:0] as analog inputs or  
GPIOs.  
0b = Channel is configured as an analog input.  
1b = Channel is configured as a GPIO.  
8.6.7 GPIO_CFG Register (Address = 0x7) [Reset = 0x0]  
GPIO_CFG is shown in Figure 8-23 and described in Table 8-19.  
Return to the Table 8-11.  
Figure 8-23. GPIO_CFG Register  
7
6
5
4
3
2
1
0
GPIO_CFG[7:0]  
R/W-0b  
Table 8-19. GPIO_CFG Register Field Descriptions  
Bit  
7-0  
Field  
GPIO_CFG[7:0]  
Type  
Reset  
Description  
R/W  
0b  
Configure GPIO[7:0] as either digital inputs or digital outputs.  
0b = GPIO is configured as digital input.  
1b = GPIO is configured as digital output.  
8.6.8 GPO_DRIVE_CFG Register (Address = 0x9) [Reset = 0x0]  
GPO_DRIVE_CFG is shown in Figure 8-24 and described in Table 8-20.  
Return to the Table 8-11.  
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Figure 8-24. GPO_DRIVE_CFG Register  
7
6
5
4
3
2
1
0
GPO_DRIVE_CFG[7:0]  
R/W-0b  
Table 8-20. GPO_DRIVE_CFG Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
GPO_DRIVE_CFG[7:0]  
R/W  
0b  
Configure digital outputs GPO[7:0] as either open-drain or push-pull  
outputs.  
0b = Digital output is open-drain; connect external pullup resistor.  
1b = Push-pull driver is used for digital output.  
8.6.9 GPO_VALUE Register (Address = 0xB) [Reset = 0x0]  
GPO_VALUE is shown in Figure 8-25 and described in Table 8-21.  
Return to the Table 8-11.  
Figure 8-25. GPO_VALUE Register  
7
6
5
4
3
2
1
0
GPO_VALUE[7:0]  
R/W-0b  
Table 8-21. GPO_VALUE Register Field Descriptions  
Bit  
7-0  
Field  
GPO_VALUE[7:0]  
Type  
Reset  
Description  
R/W  
0b  
Logic level to be set on digital outputs GPO[7:0].  
0b = Digital output is set to logic 0.  
1b = Digital output is set to logic 1.  
8.6.10 GPI_VALUE Register (Address = 0xD) [Reset = 0x0]  
GPI_VALUE is shown in Figure 8-26 and described in Table 8-22.  
Return to the Table 8-11.  
Figure 8-26. GPI_VALUE Register  
7
6
5
4
3
2
1
0
GPI_VALUE[7:0]  
R-0b  
Table 8-22. GPI_VALUE Register Field Descriptions  
Bit  
7-0  
Field  
GPI_VALUE[7:0]  
Type  
Reset  
Description  
R
0b  
This field returns the logical level of all channels including analog  
inputs, digital inputs, and digital outputs.  
0b = GPIO is at logic 0.  
1b = GPIO is at logic 1.  
8.6.11 SEQUENCE_CFG Register (Address = 0x10) [Reset = 0x0]  
SEQUENCE_CFG is shown in Figure 8-27 and described in Table 8-23.  
Return to the Table 8-11.  
Figure 8-27. SEQUENCE_CFG Register  
7
6
5
4
3
2
1
0
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Figure 8-27. SEQUENCE_CFG Register (continued)  
RESERVED  
R-0b  
SEQ_START  
RESERVED  
SEQ_MODE[1:0]  
R/W-0b  
R/W-0b  
R-0b  
Table 8-23. SEQUENCE_CFG Register Field Descriptions  
Bit  
7-5  
4
Field  
Type  
Reset  
Description  
RESERVED  
SEQ_START  
R
0b  
Reserved Bit  
R/W  
0b  
Control for start of channel sequence when using auto sequence  
mode (SEQ_MODE = 01b).  
0b = Stop channel sequencing.  
1b = Start channel sequencing in ascending order for channels  
enabled in AUTO_SEQ_CH_SEL register.  
3-2  
1-0  
RESERVED  
R
0b  
0b  
Reserved Bit  
SEQ_MODE[1:0]  
R/W  
Selects the mode of scanning of analog input channels.  
0b = Manual sequence mode; channel selected by MANUAL_CHID  
field.  
1b = Auto sequence mode; channel selected by  
AUTO_SEQ_CH_SEL.  
10b = Reserved.  
11b = Reserved.  
8.6.12 MANUAL_CH_SEL Register (Address = 0x11) [Reset = 0x0]  
MANUAL_CH_SEL is shown in Figure 8-28 and described in Table 8-24.  
Return to the Table 8-11.  
Figure 8-28. MANUAL_CH_SEL Register  
7
6
5
4
3
2
1
0
RESERVED  
R-0b  
MANUAL_CHID[3:0]  
R/W-0b  
Table 8-24. MANUAL_CH_SEL Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
3-0  
RESERVED  
R
0b  
Reserved Bit  
MANUAL_CHID[3:0]  
R/W  
0b  
In manual mode (SEQ_MODE = 00b), this field contains the 4-bit  
channel ID of the analog input channel for next ADC conversion. For  
valid ADC data, the selected channel must not be configured as  
GPIO in PIN_CFG register.  
0b = AIN0  
1b = AIN1  
10b = AIN2  
11b = AIN3  
100b = AIN4  
101b = AIN5  
110b = AIN6  
111b = AIN7  
1000b = Reserved.  
8.6.13 AUTO_SEQ_CH_SEL Register (Address = 0x12) [Reset = 0x0]  
AUTO_SEQ_CH_SEL is shown in Figure 8-29 and described in Table 8-25.  
Return to the Table 8-11.  
Figure 8-29. AUTO_SEQ_CH_SEL Register  
7
6
5
4
3
2
1
0
AUTO_SEQ_CH_SEL[7:0]  
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Figure 8-29. AUTO_SEQ_CH_SEL Register (continued)  
R/W-0b  
Table 8-25. AUTO_SEQ_CH_SEL Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
AUTO_SEQ_CH_SEL[7:0] R/W  
0b  
Select analog input channels AIN[7:0] in for auto sequencing mode.  
0b = Analog input channel is not enabled in scanning sequence.  
1b = Analog input channel is enabled in scanning sequence.  
8.6.14 ALERT_CH_SEL Register (Address = 0x14) [Reset = 0x0]  
ALERT_CH_SEL is shown in Figure 8-30 and described in Table 8-26.  
Return to the Table 8-11.  
Figure 8-30. ALERT_CH_SEL Register  
7
6
5
4
3
2
1
0
ALERT_CH_SEL[7:0]  
R/W-0b  
Table 8-26. ALERT_CH_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
ALERT_CH_SEL[7:0]  
R/W  
0b  
Select channels for which the alert flags can assert the ALERT pin.  
0b = Event flags for this channel do not assert the ALERT pin.  
1b = Event flags for this channel assert the ALERT pin.  
8.6.15 ALERT_FUNC_SEL Register (Address = 0x16) [Reset = 0x0]  
ALERT_FUNC_SEL is shown in Figure 8-31 and described in Table 8-27.  
Return to the Table 8-11.  
Figure 8-31. ALERT_FUNC_SEL Register  
7
6
5
4
3
2
1
0
RESERVED  
R-0b  
ALERT_CRCIN  
R/W-0b  
Table 8-27. ALERT_FUNC_SEL Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-1  
0
RESERVED  
R
0b  
Reserved Bit  
ALERT_CRCIN  
R/W  
0b  
Enable or disable the alert notification for CRC error on input data  
(CRCERR_IN = 1b).  
0b = ALERT pin is not asserted when CRCERR_IN = 1b.  
1b = ALERT pin is asserted when CRCERR_IN = 1b. Clear  
CRCERR_IN for deasserting the ALERT pin.  
8.6.16 ALERT_PIN_CFG Register (Address = 0x17) [Reset = 0x0]  
ALERT_PIN_CFG is shown in Figure 8-32 and described in Table 8-28.  
Return to the Table 8-11.  
Figure 8-32. ALERT_PIN_CFG Register  
7
6
5
4
3
2
1
0
RESERVED  
ALERT_DRIVE  
ALERT_LOGIC[1:0]  
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Figure 8-32. ALERT_PIN_CFG Register (continued)  
R-0b  
R/W-0b  
R/W-0b  
Table 8-28. ALERT_PIN_CFG Register Field Descriptions  
Bit  
7-3  
2
Field  
Type  
Reset  
Description  
RESERVED  
ALERT_DRIVE  
R
0b  
Reserved Bit  
R/W  
0b  
Configure output drive of the ALERT pin.  
0b = Open-drain output. Connect external pullup resistor.  
1b = Push-pull output.  
1-0  
ALERT_LOGIC[1:0]  
R/W  
0b  
Configure how ALERT pin is asserted.  
0b = Active low.  
1b = Active high.  
10b = Pulsed low (one logic low pulse every time a bit in  
EVENT_FLAG is set to 1b).  
11b = Pulsed high (one logic high pulse every time a bit in  
EVENT_FLAG is set to 1b).  
8.6.17 EVENT_FLAG Register (Address = 0x18) [Reset = 0x0]  
EVENT_FLAG is shown in Figure 8-33 and described in Table 8-29.  
Return to the Table 8-11.  
Figure 8-33. EVENT_FLAG Register  
7
6
5
4
3
2
1
0
EVENT_FLAG[7:0]  
R-0b  
Table 8-29. EVENT_FLAG Register Field Descriptions  
Bit  
7-0  
Field  
EVENT_FLAG[7:0]  
Type  
Reset  
Description  
R
0b  
Event flags indicating digital window comparator status for AIN/  
GPIO[7:0]. Clear individual bits of EVENT_HIGH_FLAG or  
EVENT_LOW_FLAG registers to clear the corresponding bit in this  
register.  
0b = Event condition not detected.  
1b = Event condition detected.  
8.6.18 EVENT_HIGH_FLAG Register (Address = 0x1A) [Reset = 0x0]  
EVENT_HIGH_FLAG is shown in Figure 8-34 and described in Table 8-30.  
Return to the Table 8-11.  
Figure 8-34. EVENT_HIGH_FLAG Register  
7
6
5
4
3
2
1
0
EVENT_HIGH_FLAG[7:0]  
R/W-0b  
Table 8-30. EVENT_HIGH_FLAG Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
EVENT_HIGH_FLAG[7:0] R/W  
0b  
Event flag corresponding to high threshold of analog input or logic 1  
on digital input on AIN/GPIO[7:0]. Write 1b to clear this flag.  
0b = No alert condition detected.  
1b = Either high threshold was exceeded (analog input) or logic 1  
was detected (digital input).  
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8.6.19 EVENT_LOW_FLAG Register (Address = 0x1C) [Reset = 0x0]  
EVENT_LOW_FLAG is shown in Figure 8-35 and described in Table 8-31.  
Return to the Table 8-11.  
Figure 8-35. EVENT_LOW_FLAG Register  
7
6
5
4
3
2
1
0
EVENT_LOW_FLAG[7:0]  
R/W-0b  
Table 8-31. EVENT_LOW_FLAG Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
EVENT_LOW_FLAG[7:0] R/W  
0b  
Event orresponding to low threshold of analog input or logic 0 on  
digital input on AIN/GPIO[7:0]. Write 1b to clear this flag.  
0b = No Event condition detected.  
1b = Either low threshold was exceeded (analog input) or logic 0 was  
detected (digital input).  
8.6.20 EVENT_RGN Register (Address = 0x1E) [Reset = 0x0]  
EVENT_RGN is shown in Figure 8-36 and described in Table 8-32.  
Return to the Table 8-11.  
Figure 8-36. EVENT_RGN Register  
7
6
5
4
3
2
1
0
EVENT_RGN[7:0]  
R/W-0b  
Table 8-32. EVENT_RGN Register Field Descriptions  
Bit  
7-0  
Field  
EVENT_RGN[7:0]  
Type  
Reset  
Description  
R/W  
0b  
Choice of region used in monitoring analog and digital inputs AIN/  
GPIO[7:0].  
0b = Event flag is set if: (conversion result < low threshold) or  
(conversion result > high threshold). For digital inputs, logic 1 sets  
the alert flag.  
1b = Event flag is set if: (low threshold > conversion result < high  
threshold). For digital inputs, logic 0 sets the eventt flag.  
8.6.21 HYSTERESIS_CH0 Register (Address = 0x20) [Reset = 0xF0]  
HYSTERESIS_CH0 is shown in Figure 8-37 and described in Table 8-33.  
Return to the Table 8-11.  
Figure 8-37. HYSTERESIS_CH0 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH0_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH0[3:0]  
R/W-0b  
Table 8-33. HYSTERESIS_CH0 Register Field Descriptions  
Bit  
7-4  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH0 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
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Table 8-33. HYSTERESIS_CH0 Register Field Descriptions (continued)  
Bit  
Field  
Type  
Reset  
Description  
3-0  
HYSTERESIS_CH0[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.22 HIGH_TH_CH0 Register (Address = 0x21) [Reset = 0xFF]  
HIGH_TH_CH0 is shown in Figure 8-38 and described in Table 8-34.  
Return to the Table 8-11.  
Figure 8-38. HIGH_TH_CH0 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH0_MSB[7:0]  
R/W-11111111b  
Table 8-34. HIGH_TH_CH0 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH0 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.23 EVENT_COUNT_CH0 Register (Address = 0x22) [Reset = 0x0]  
EVENT_COUNT_CH0 is shown in Figure 8-39 and described in Table 8-35.  
Return to the Table 8-11.  
Figure 8-39. EVENT_COUNT_CH0 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH0_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH0[3:0]  
R/W-0b  
Table 8-35. EVENT_COUNT_CH0 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH0 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH0[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.24 LOW_TH_CH0 Register (Address = 0x23) [Reset = 0x0]  
LOW_TH_CH0 is shown in Figure 8-40 and described in Table 8-36.  
Return to the Table 8-11.  
Figure 8-40. LOW_TH_CH0 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH0_MSB[7:0]  
R/W-0b  
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Table 8-36. LOW_TH_CH0 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
LOW_THRESHOLD_CH0 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.25 HYSTERESIS_CH1 Register (Address = 0x24) [Reset = 0xF0]  
HYSTERESIS_CH1 is shown in Figure 8-41 and described in Table 8-37.  
Return to the Table 8-11.  
Figure 8-41. HYSTERESIS_CH1 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH1_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH1[3:0]  
R/W-0b  
Table 8-37. HYSTERESIS_CH1 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
HIGH_THRESHOLD_CH1 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
HYSTERESIS_CH1[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.26 HIGH_TH_CH1 Register (Address = 0x25) [Reset = 0xFF]  
HIGH_TH_CH1 is shown in Figure 8-42 and described in Table 8-38.  
Return to the Table 8-11.  
Figure 8-42. HIGH_TH_CH1 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH1_MSB[7:0]  
R/W-11111111b  
Table 8-38. HIGH_TH_CH1 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH1 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.27 EVENT_COUNT_CH1 Register (Address = 0x26) [Reset = 0x0]  
EVENT_COUNT_CH1 is shown in Figure 8-43 and described in Table 8-39.  
Return to the Table 8-11.  
Figure 8-43. EVENT_COUNT_CH1 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH1_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH1[3:0]  
R/W-0b  
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Table 8-39. EVENT_COUNT_CH1 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH1 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH1[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.28 LOW_TH_CH1 Register (Address = 0x27) [Reset = 0x0]  
LOW_TH_CH1 is shown in Figure 8-44 and described in Table 8-40.  
Return to the Table 8-11.  
Figure 8-44. LOW_TH_CH1 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH1_MSB[7:0]  
R/W-0b  
Table 8-40. LOW_TH_CH1 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LOW_THRESHOLD_CH1 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.29 HYSTERESIS_CH2 Register (Address = 0x28) [Reset = 0xF0]  
HYSTERESIS_CH2 is shown in Figure 8-45 and described in Table 8-41.  
Return to the Table 8-11.  
Figure 8-45. HYSTERESIS_CH2 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH2_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH2[3:0]  
R/W-0b  
Table 8-41. HYSTERESIS_CH2 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
HIGH_THRESHOLD_CH2 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
HYSTERESIS_CH2[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.30 HIGH_TH_CH2 Register (Address = 0x29) [Reset = 0xFF]  
HIGH_TH_CH2 is shown in Figure 8-46 and described in Table 8-42.  
Return to the Table 8-11.  
Figure 8-46. HIGH_TH_CH2 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH2_MSB[7:0]  
R/W-11111111b  
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Table 8-42. HIGH_TH_CH2 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
HIGH_THRESHOLD_CH2 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.31 EVENT_COUNT_CH2 Register (Address = 0x2A) [Reset = 0x0]  
EVENT_COUNT_CH2 is shown in Figure 8-47 and described in Table 8-43.  
Return to the Table 8-11.  
Figure 8-47. EVENT_COUNT_CH2 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH2_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH2[3:0]  
R/W-0b  
Table 8-43. EVENT_COUNT_CH2 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH2 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH2[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.32 LOW_TH_CH2 Register (Address = 0x2B) [Reset = 0x0]  
LOW_TH_CH2 is shown in Figure 8-48 and described in Table 8-44.  
Return to the Table 8-11.  
Figure 8-48. LOW_TH_CH2 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH2_MSB[7:0]  
R/W-0b  
Table 8-44. LOW_TH_CH2 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LOW_THRESHOLD_CH2 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.33 HYSTERESIS_CH3 Register (Address = 0x2C) [Reset = 0xF0]  
HYSTERESIS_CH3 is shown in Figure 8-49 and described in Table 8-45.  
Return to the Table 8-11.  
Figure 8-49. HYSTERESIS_CH3 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH3_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH3[3:0]  
R/W-0b  
Table 8-45. HYSTERESIS_CH3 Register Field Descriptions  
Bit  
7-4  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH3 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
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Table 8-45. HYSTERESIS_CH3 Register Field Descriptions (continued)  
Bit  
Field  
Type  
Reset  
Description  
3-0  
HYSTERESIS_CH3[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.34 HIGH_TH_CH3 Register (Address = 0x2D) [Reset = 0xFF]  
HIGH_TH_CH3 is shown in Figure 8-50 and described in Table 8-46.  
Return to the Table 8-11.  
Figure 8-50. HIGH_TH_CH3 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH3_MSB[7:0]  
R/W-11111111b  
Table 8-46. HIGH_TH_CH3 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH3 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.35 EVENT_COUNT_CH3 Register (Address = 0x2E) [Reset = 0x0]  
EVENT_COUNT_CH3 is shown in Figure 8-51 and described in Table 8-47.  
Return to the Table 8-11.  
Figure 8-51. EVENT_COUNT_CH3 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH3_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH3[3:0]  
R/W-0b  
Table 8-47. EVENT_COUNT_CH3 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH3 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH3[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.36 LOW_TH_CH3 Register (Address = 0x2F) [Reset = 0x0]  
LOW_TH_CH3 is shown in Figure 8-52 and described in Table 8-48.  
Return to the Table 8-11.  
Figure 8-52. LOW_TH_CH3 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH3_MSB[7:0]  
R/W-0b  
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Table 8-48. LOW_TH_CH3 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
LOW_THRESHOLD_CH3 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.37 HYSTERESIS_CH4 Register (Address = 0x30) [Reset = 0xF0]  
HYSTERESIS_CH4 is shown in Figure 8-53 and described in Table 8-49.  
Return to the Table 8-11.  
Figure 8-53. HYSTERESIS_CH4 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH4_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH4[3:0]  
R/W-0b  
Table 8-49. HYSTERESIS_CH4 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
HIGH_THRESHOLD_CH4 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
HYSTERESIS_CH4[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.38 HIGH_TH_CH4 Register (Address = 0x31) [Reset = 0xFF]  
HIGH_TH_CH4 is shown in Figure 8-54 and described in Table 8-50.  
Return to the Table 8-11.  
Figure 8-54. HIGH_TH_CH4 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH4_MSB[7:0]  
R/W-11111111b  
Table 8-50. HIGH_TH_CH4 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH4 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.39 EVENT_COUNT_CH4 Register (Address = 0x32) [Reset = 0x0]  
EVENT_COUNT_CH4 is shown in Figure 8-55 and described in Table 8-51.  
Return to the Table 8-11.  
Figure 8-55. EVENT_COUNT_CH4 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH4_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH4[3:0]  
R/W-0b  
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Table 8-51. EVENT_COUNT_CH4 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH4 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH4[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.40 LOW_TH_CH4 Register (Address = 0x33) [Reset = 0x0]  
LOW_TH_CH4 is shown in Figure 8-56 and described in Table 8-52.  
Return to the Table 8-11.  
Figure 8-56. LOW_TH_CH4 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH4_MSB[7:0]  
R/W-0b  
Table 8-52. LOW_TH_CH4 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LOW_THRESHOLD_CH4 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.41 HYSTERESIS_CH5 Register (Address = 0x34) [Reset = 0xF0]  
HYSTERESIS_CH5 is shown in Figure 8-57 and described in Table 8-53.  
Return to the Table 8-11.  
Figure 8-57. HYSTERESIS_CH5 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH5_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH5[3:0]  
R/W-0b  
Table 8-53. HYSTERESIS_CH5 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
HIGH_THRESHOLD_CH5 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
HYSTERESIS_CH5[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.42 HIGH_TH_CH5 Register (Address = 0x35) [Reset = 0xFF]  
HIGH_TH_CH5 is shown in Figure 8-58 and described in Table 8-54.  
Return to the Table 8-11.  
Figure 8-58. HIGH_TH_CH5 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH5_MSB[7:0]  
R/W-11111111b  
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Table 8-54. HIGH_TH_CH5 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
HIGH_THRESHOLD_CH5 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.43 EVENT_COUNT_CH5 Register (Address = 0x36) [Reset = 0x0]  
EVENT_COUNT_CH5 is shown in Figure 8-59 and described in Table 8-55.  
Return to the Table 8-11.  
Figure 8-59. EVENT_COUNT_CH5 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH5_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH5[3:0]  
R/W-0b  
Table 8-55. EVENT_COUNT_CH5 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH5 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH5[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.44 LOW_TH_CH5 Register (Address = 0x37) [Reset = 0x0]  
LOW_TH_CH5 is shown in Figure 8-60 and described in Table 8-56.  
Return to the Table 8-11.  
Figure 8-60. LOW_TH_CH5 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH5_MSB[7:0]  
R/W-0b  
Table 8-56. LOW_TH_CH5 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LOW_THRESHOLD_CH5 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.45 HYSTERESIS_CH6 Register (Address = 0x38) [Reset = 0xF0]  
HYSTERESIS_CH6 is shown in Figure 8-61 and described in Table 8-57.  
Return to the Table 8-11.  
Figure 8-61. HYSTERESIS_CH6 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH6_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH6[3:0]  
R/W-0b  
Table 8-57. HYSTERESIS_CH6 Register Field Descriptions  
Bit  
7-4  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH6 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
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Table 8-57. HYSTERESIS_CH6 Register Field Descriptions (continued)  
Bit  
Field  
Type  
Reset  
Description  
3-0  
HYSTERESIS_CH6[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.46 HIGH_TH_CH6 Register (Address = 0x39) [Reset = 0xFF]  
HIGH_TH_CH6 is shown in Figure 8-62 and described in Table 8-58.  
Return to the Table 8-11.  
Figure 8-62. HIGH_TH_CH6 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH6_MSB[7:0]  
R/W-11111111b  
Table 8-58. HIGH_TH_CH6 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH6 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.47 EVENT_COUNT_CH6 Register (Address = 0x3A) [Reset = 0x0]  
EVENT_COUNT_CH6 is shown in Figure 8-63 and described in Table 8-59.  
Return to the Table 8-11.  
Figure 8-63. EVENT_COUNT_CH6 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH6_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH6[3:0]  
R/W-0b  
Table 8-59. EVENT_COUNT_CH6 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH6 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH6[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.48 LOW_TH_CH6 Register (Address = 0x3B) [Reset = 0x0]  
LOW_TH_CH6 is shown in Figure 8-64 and described in Table 8-60.  
Return to the Table 8-11.  
Figure 8-64. LOW_TH_CH6 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH6_MSB[7:0]  
R/W-0b  
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Table 8-60. LOW_TH_CH6 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
LOW_THRESHOLD_CH6 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.49 HYSTERESIS_CH7 Register (Address = 0x3C) [Reset = 0xF0]  
HYSTERESIS_CH7 is shown in Figure 8-65 and described in Table 8-61.  
Return to the Table 8-11.  
Figure 8-65. HYSTERESIS_CH7 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH7_LSB[3:0]  
R/W-1111b  
HYSTERESIS_CH7[3:0]  
R/W-0b  
Table 8-61. HYSTERESIS_CH7 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
HIGH_THRESHOLD_CH7 R/W  
_LSB[3:0]  
1111b  
Lower 4-bits of high threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
HYSTERESIS_CH7[3:0]  
R/W  
0b  
4-bit hysteresis for high and low thresholds. This 4-bit hysteris is left  
shifted 3 times and applied on the lower 7-bits of the threshold. Total  
hysteresis = 7-bits [4-bits, 000b]  
8.6.50 HIGH_TH_CH7 Register (Address = 0x3D) [Reset = 0xFF]  
HIGH_TH_CH7 is shown in Figure 8-66 and described in Table 8-62.  
Return to the Table 8-11.  
Figure 8-66. HIGH_TH_CH7 Register  
7
6
5
4
3
2
1
0
HIGH_THRESHOLD_CH7_MSB[7:0]  
R/W-11111111b  
Table 8-62. HIGH_TH_CH7 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
HIGH_THRESHOLD_CH7 R/W  
_MSB[7:0]  
11111111b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.51 EVENT_COUNT_CH7 Register (Address = 0x3E) [Reset = 0x0]  
EVENT_COUNT_CH7 is shown in Figure 8-67 and described in Table 8-63.  
Return to the Table 8-11.  
Figure 8-67. EVENT_COUNT_CH7 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH7_LSB[3:0]  
R/W-0b  
EVENT_COUNT_CH7[3:0]  
R/W-0b  
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Table 8-63. EVENT_COUNT_CH7 Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-4  
LOW_THRESHOLD_CH7 R/W  
_LSB[3:0]  
0b  
Lower 4-bits of low threshold for analog input. These bits are  
compared with bits 3:0 of ADC conversion result.  
3-0  
EVENT_COUNT_CH7[3:0 R/W  
]
0b  
Configuration for checking 'n+1' consecutive samples above  
threshold before setting event flag.  
8.6.52 LOW_TH_CH7 Register (Address = 0x3F) [Reset = 0x0]  
LOW_TH_CH7 is shown in Figure 8-68 and described in Table 8-64.  
Return to the Table 8-11.  
Figure 8-68. LOW_TH_CH7 Register  
7
6
5
4
3
2
1
0
LOW_THRESHOLD_CH7_MSB[7:0]  
R/W-0b  
Table 8-64. LOW_TH_CH7 Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LOW_THRESHOLD_CH7 R/W  
_MSB[7:0]  
0b  
MSB aligned high threshold for analog input. These bits are  
compared with top 8 bits of ADC conversion result.  
8.6.53 MAX_CH0_LSB Register (Address = 0x60) [Reset = 0x0]  
MAX_CH0_LSB is shown in Figure 8-69 and described in Table 8-65.  
Return to the Table 8-11.  
Figure 8-69. MAX_CH0_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH0_LSB[7:0]  
R-0b  
Table 8-65. MAX_CH0_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH0_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.54 MAX_CH0_MSB Register (Address = 0x61) [Reset = 0x0]  
MAX_CH0_MSB is shown in Figure 8-70 and described in Table 8-66.  
Return to the Table 8-11.  
Figure 8-70. MAX_CH0_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH0_MSB[7:0]  
R-0b  
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Table 8-66. MAX_CH0_MSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MAX_VALUE_CH0_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.55 MAX_CH1_LSB Register (Address = 0x62) [Reset = 0x0]  
MAX_CH1_LSB is shown in Figure 8-71 and described in Table 8-67.  
Return to the Table 8-11.  
Figure 8-71. MAX_CH1_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH1_LSB[7:0]  
R-0b  
Table 8-67. MAX_CH1_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH1_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.56 MAX_CH1_MSB Register (Address = 0x63) [Reset = 0x0]  
MAX_CH1_MSB is shown in Figure 8-72 and described in Table 8-68.  
Return to the Table 8-11.  
Figure 8-72. MAX_CH1_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH1_MSB[7:0]  
R-0b  
Table 8-68. MAX_CH1_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH1_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.57 MAX_CH2_LSB Register (Address = 0x64) [Reset = 0x0]  
MAX_CH2_LSB is shown in Figure 8-73 and described in Table 8-69.  
Return to the Table 8-11.  
Figure 8-73. MAX_CH2_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH2_LSB[7:0]  
R-0b  
Table 8-69. MAX_CH2_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH2_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
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8.6.58 MAX_CH2_MSB Register (Address = 0x65) [Reset = 0x0]  
MAX_CH2_MSB is shown in Figure 8-74 and described in Table 8-70.  
Return to the Table 8-11.  
Figure 8-74. MAX_CH2_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH2_MSB[7:0]  
R-0b  
Table 8-70. MAX_CH2_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH2_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.59 MAX_CH3_LSB Register (Address = 0x66) [Reset = 0x0]  
MAX_CH3_LSB is shown in Figure 8-75 and described in Table 8-71.  
Return to the Table 8-11.  
Figure 8-75. MAX_CH3_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH3_LSB[7:0]  
R-0b  
Table 8-71. MAX_CH3_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH3_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.60 MAX_CH3_MSB Register (Address = 0x67) [Reset = 0x0]  
MAX_CH3_MSB is shown in Figure 8-76 and described in Table 8-72.  
Return to the Table 8-11.  
Figure 8-76. MAX_CH3_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH3_MSB[7:0]  
R-0b  
Table 8-72. MAX_CH3_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH3_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.61 MAX_CH4_LSB Register (Address = 0x68) [Reset = 0x0]  
MAX_CH4_LSB is shown in Figure 8-77 and described in Table 8-73.  
Return to the Table 8-11.  
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Figure 8-77. MAX_CH4_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH4_LSB[7:0]  
R-0b  
Table 8-73. MAX_CH4_LSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MAX_VALUE_CH4_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.62 MAX_CH4_MSB Register (Address = 0x69) [Reset = 0x0]  
MAX_CH4_MSB is shown in Figure 8-78 and described in Table 8-74.  
Return to the Table 8-11.  
Figure 8-78. MAX_CH4_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH4_MSB[7:0]  
R-0b  
Table 8-74. MAX_CH4_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH4_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.63 MAX_CH5_LSB Register (Address = 0x6A) [Reset = 0x0]  
MAX_CH5_LSB is shown in Figure 8-79 and described in Table 8-75.  
Return to the Table 8-11.  
Figure 8-79. MAX_CH5_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH5_LSB[7:0]  
R-0b  
Table 8-75. MAX_CH5_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH5_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.64 MAX_CH5_MSB Register (Address = 0x6B) [Reset = 0x0]  
MAX_CH5_MSB is shown in Figure 8-80 and described in Table 8-76.  
Return to the Table 8-11.  
Figure 8-80. MAX_CH5_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH5_MSB[7:0]  
R-0b  
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Table 8-76. MAX_CH5_MSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MAX_VALUE_CH5_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.65 MAX_CH6_LSB Register (Address = 0x6C) [Reset = 0x0]  
MAX_CH6_LSB is shown in Figure 8-81 and described in Table 8-77.  
Return to the Table 8-11.  
Figure 8-81. MAX_CH6_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH6_LSB[7:0]  
R-0b  
Table 8-77. MAX_CH6_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH6_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.66 MAX_CH6_MSB Register (Address = 0x6D) [Reset = 0x0]  
MAX_CH6_MSB is shown in Figure 8-82 and described in Table 8-78.  
Return to the Table 8-11.  
Figure 8-82. MAX_CH6_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH6_MSB[7:0]  
R-0b  
Table 8-78. MAX_CH6_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH6_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.67 MAX_CH7_LSB Register (Address = 0x6E) [Reset = 0x0]  
MAX_CH7_LSB is shown in Figure 8-83 and described in Table 8-79.  
Return to the Table 8-11.  
Figure 8-83. MAX_CH7_LSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH7_LSB[7:0]  
R-0b  
Table 8-79. MAX_CH7_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH7_LSB[7 R  
:0]  
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
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8.6.68 MAX_CH7_MSB Register (Address = 0x6F) [Reset = 0x0]  
MAX_CH7_MSB is shown in Figure 8-84 and described in Table 8-80.  
Return to the Table 8-11.  
Figure 8-84. MAX_CH7_MSB Register  
7
6
5
4
3
2
1
0
MAX_VALUE_CH7_MSB[7:0]  
R-0b  
Table 8-80. MAX_CH7_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MAX_VALUE_CH7_MSB[  
7:0]  
R
0b  
Maximum code recorded on analog input channel from the last time  
this register was read. Reading the register resets the value to 0.  
8.6.69 MIN_CH0_LSB Register (Address = 0x80) [Reset = 0xFF]  
MIN_CH0_LSB is shown in Figure 8-85 and described in Table 8-81.  
Return to the Table 8-11.  
Figure 8-85. MIN_CH0_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH0_LSB[7:0]  
R-11111111b  
Table 8-81. MIN_CH0_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH0_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.70 MIN_CH0_MSB Register (Address = 0x81) [Reset = 0xFF]  
MIN_CH0_MSB is shown in Figure 8-86 and described in Table 8-82.  
Return to the Table 8-11.  
Figure 8-86. MIN_CH0_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH0_MSB[7:0]  
R-11111111b  
Table 8-82. MIN_CH0_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH0_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.71 MIN_CH1_LSB Register (Address = 0x82) [Reset = 0xFF]  
MIN_CH1_LSB is shown in Figure 8-87 and described in Table 8-83.  
Return to the Table 8-11.  
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Figure 8-87. MIN_CH1_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH1_LSB[7:0]  
R-11111111b  
Table 8-83. MIN_CH1_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH1_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.72 MIN_CH1_MSB Register (Address = 0x83) [Reset = 0xFF]  
MIN_CH1_MSB is shown in Figure 8-88 and described in Table 8-84.  
Return to the Table 8-11.  
Figure 8-88. MIN_CH1_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH1_MSB[7:0]  
R-11111111b  
Table 8-84. MIN_CH1_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH1_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.73 MIN_CH2_LSB Register (Address = 0x84) [Reset = 0xFF]  
MIN_CH2_LSB is shown in Figure 8-89 and described in Table 8-85.  
Return to the Table 8-11.  
Figure 8-89. MIN_CH2_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH2_LSB[7:0]  
R-11111111b  
Table 8-85. MIN_CH2_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH2_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.74 MIN_CH2_MSB Register (Address = 0x85) [Reset = 0xFF]  
MIN_CH2_MSB is shown in Figure 8-90 and described in Table 8-86.  
Return to the Table 8-11.  
Figure 8-90. MIN_CH2_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH2_MSB[7:0]  
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Figure 8-90. MIN_CH2_MSB Register (continued)  
R-11111111b  
Table 8-86. MIN_CH2_MSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MIN_VALUE_CH2_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.75 MIN_CH3_LSB Register (Address = 0x86) [Reset = 0xFF]  
MIN_CH3_LSB is shown in Figure 8-91 and described in Table 8-87.  
Return to the Table 8-11.  
Figure 8-91. MIN_CH3_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH3_LSB[7:0]  
R-11111111b  
Table 8-87. MIN_CH3_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH3_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.76 MIN_CH3_MSB Register (Address = 0x87) [Reset = 0xFF]  
MIN_CH3_MSB is shown in Figure 8-92 and described in Table 8-88.  
Return to the Table 8-11.  
Figure 8-92. MIN_CH3_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH3_MSB[7:0]  
R-11111111b  
Table 8-88. MIN_CH3_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH3_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.77 MIN_CH4_LSB Register (Address = 0x88) [Reset = 0xFF]  
MIN_CH4_LSB is shown in Figure 8-93 and described in Table 8-89.  
Return to the Table 8-11.  
Figure 8-93. MIN_CH4_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH4_LSB[7:0]  
R-11111111b  
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Table 8-89. MIN_CH4_LSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MIN_VALUE_CH4_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.78 MIN_CH4_MSB Register (Address = 0x89) [Reset = 0xFF]  
MIN_CH4_MSB is shown in Figure 8-94 and described in Table 8-90.  
Return to the Table 8-11.  
Figure 8-94. MIN_CH4_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH4_MSB[7:0]  
R-11111111b  
Table 8-90. MIN_CH4_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH4_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.79 MIN_CH5_LSB Register (Address = 0x8A) [Reset = 0xFF]  
MIN_CH5_LSB is shown in Figure 8-95 and described in Table 8-91.  
Return to the Table 8-11.  
Figure 8-95. MIN_CH5_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH5_LSB[7:0]  
R-11111111b  
Table 8-91. MIN_CH5_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH5_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.80 MIN_CH5_MSB Register (Address = 0x8B) [Reset = 0xFF]  
MIN_CH5_MSB is shown in Figure 8-96 and described in Table 8-92.  
Return to the Table 8-11.  
Figure 8-96. MIN_CH5_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH5_MSB[7:0]  
R-11111111b  
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Table 8-92. MIN_CH5_MSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MIN_VALUE_CH5_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.81 MIN_CH6_LSB Register (Address = 0x8C) [Reset = 0xFF]  
MIN_CH6_LSB is shown in Figure 8-97 and described in Table 8-93.  
Return to the Table 8-11.  
Figure 8-97. MIN_CH6_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH6_LSB[7:0]  
R-11111111b  
Table 8-93. MIN_CH6_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH6_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.82 MIN_CH6_MSB Register (Address = 0x8D) [Reset = 0xFF]  
MIN_CH6_MSB is shown in Figure 8-98 and described in Table 8-94.  
Return to the Table 8-11.  
Figure 8-98. MIN_CH6_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH6_MSB[7:0]  
R-11111111b  
Table 8-94. MIN_CH6_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH6_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.83 MIN_CH7_LSB Register (Address = 0x8E) [Reset = 0xFF]  
MIN_CH7_LSB is shown in Figure 8-99 and described in Table 8-95.  
Return to the Table 8-11.  
Figure 8-99. MIN_CH7_LSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH7_LSB[7:0]  
R-11111111b  
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Table 8-95. MIN_CH7_LSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
MIN_VALUE_CH7_LSB[7: R  
0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.84 MIN_CH7_MSB Register (Address = 0x8F) [Reset = 0xFF]  
MIN_CH7_MSB is shown in Figure 8-100 and described in Table 8-96.  
Return to the Table 8-11.  
Figure 8-100. MIN_CH7_MSB Register  
7
6
5
4
3
2
1
0
MIN_VALUE_CH7_MSB[7:0]  
R-11111111b  
Table 8-96. MIN_CH7_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
MIN_VALUE_CH7_MSB[7 R  
:0]  
11111111b  
Minimum code recorded on the analog input channel from the last  
time this register was read. Reading the register resets the value to  
0xFF.  
8.6.85 RECENT_CH0_LSB Register (Address = 0xA0) [Reset = 0x0]  
RECENT_CH0_LSB is shown in Figure 8-101 and described in Table 8-97.  
Return to the Table 8-11.  
Figure 8-101. RECENT_CH0_LSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH0_LSB[7:0]  
R-0b  
Table 8-97. RECENT_CH0_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH0_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.86 RECENT_CH0_MSB Register (Address = 0xA1) [Reset = 0x0]  
RECENT_CH0_MSB is shown in Figure 8-102 and described in Table 8-98.  
Return to the Table 8-11.  
Figure 8-102. RECENT_CH0_MSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH0_MSB[7:0]  
R-0b  
Table 8-98. RECENT_CH0_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH0_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
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8.6.87 RECENT_CH1_LSB Register (Address = 0xA2) [Reset = 0x0]  
RECENT_CH1_LSB is shown in Figure 8-103 and described in Table 8-99.  
Return to the Table 8-11.  
Figure 8-103. RECENT_CH1_LSB Register  
7
6
5
4
3
2
1
0
0
0
LAST_VALUE_CH1_LSB[7:0]  
R-0b  
Table 8-99. RECENT_CH1_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH1_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.88 RECENT_CH1_MSB Register (Address = 0xA3) [Reset = 0x0]  
RECENT_CH1_MSB is shown in Figure 8-104 and described in Table 8-100.  
Return to the Table 8-11.  
Figure 8-104. RECENT_CH1_MSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH1_MSB[7:0]  
R-0b  
Table 8-100. RECENT_CH1_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH1_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.89 RECENT_CH2_LSB Register (Address = 0xA4) [Reset = 0x0]  
RECENT_CH2_LSB is shown in Figure 8-105 and described in Table 8-101.  
Return to the Table 8-11.  
Figure 8-105. RECENT_CH2_LSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH2_LSB[7:0]  
R-0b  
Table 8-101. RECENT_CH2_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH2_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.90 RECENT_CH2_MSB Register (Address = 0xA5) [Reset = 0x0]  
RECENT_CH2_MSB is shown in Figure 8-106 and described in Table 8-102.  
Return to the Table 8-11.  
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Figure 8-106. RECENT_CH2_MSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH2_MSB[7:0]  
R-0b  
Table 8-102. RECENT_CH2_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH2_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.91 RECENT_CH3_LSB Register (Address = 0xA6) [Reset = 0x0]  
RECENT_CH3_LSB is shown in Figure 8-107 and described in Table 8-103.  
Return to the Table 8-11.  
Figure 8-107. RECENT_CH3_LSB Register  
7
6
5
4
3
2
1
0
0
0
LAST_VALUE_CH3_LSB[7:0]  
R-0b  
Table 8-103. RECENT_CH3_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH3_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.92 RECENT_CH3_MSB Register (Address = 0xA7) [Reset = 0x0]  
RECENT_CH3_MSB is shown in Figure 8-108 and described in Table 8-104.  
Return to the Table 8-11.  
Figure 8-108. RECENT_CH3_MSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH3_MSB[7:0]  
R-0b  
Table 8-104. RECENT_CH3_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH3_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.93 RECENT_CH4_LSB Register (Address = 0xA8) [Reset = 0x0]  
RECENT_CH4_LSB is shown in Figure 8-109 and described in Table 8-105.  
Return to the Table 8-11.  
Figure 8-109. RECENT_CH4_LSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH4_LSB[7:0]  
R-0b  
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Table 8-105. RECENT_CH4_LSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
LAST_VALUE_CH4_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.94 RECENT_CH4_MSB Register (Address = 0xA9) [Reset = 0x0]  
RECENT_CH4_MSB is shown in Figure 8-110 and described in Table 8-106.  
Return to the Table 8-11.  
Figure 8-110. RECENT_CH4_MSB Register  
7
6
5
4
3
2
1
0
0
0
LAST_VALUE_CH4_MSB[7:0]  
R-0b  
Table 8-106. RECENT_CH4_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH4_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.95 RECENT_CH5_LSB Register (Address = 0xAA) [Reset = 0x0]  
RECENT_CH5_LSB is shown in Figure 8-111 and described in Table 8-107.  
Return to the Table 8-11.  
Figure 8-111. RECENT_CH5_LSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH5_LSB[7:0]  
R-0b  
Table 8-107. RECENT_CH5_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH5_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.96 RECENT_CH5_MSB Register (Address = 0xAB) [Reset = 0x0]  
RECENT_CH5_MSB is shown in Figure 8-112 and described in Table 8-108.  
Return to the Table 8-11.  
Figure 8-112. RECENT_CH5_MSB Register  
5
7
6
4
3
2
1
LAST_VALUE_CH5_MSB[7:0]  
R-0b  
Table 8-108. RECENT_CH5_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH5_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
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8.6.97 RECENT_CH6_LSB Register (Address = 0xAC) [Reset = 0x0]  
RECENT_CH6_LSB is shown in Figure 8-113 and described in Table 8-109.  
Return to the Table 8-11.  
Figure 8-113. RECENT_CH6_LSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH6_LSB[7:0]  
R-0b  
Table 8-109. RECENT_CH6_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH6_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.98 RECENT_CH6_MSB Register (Address = 0xAD) [Reset = 0x0]  
RECENT_CH6_MSB is shown in Figure 8-114 and described in Table 8-110.  
Return to the Table 8-11.  
Figure 8-114. RECENT_CH6_MSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH6_MSB[7:0]  
R-0b  
Table 8-110. RECENT_CH6_MSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH6_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.99 RECENT_CH7_LSB Register (Address = 0xAE) [Reset = 0x0]  
RECENT_CH7_LSB is shown in Figure 8-115 and described in Table 8-111.  
Return to the Table 8-11.  
Figure 8-115. RECENT_CH7_LSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH7_LSB[7:0]  
R-0b  
Table 8-111. RECENT_CH7_LSB Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
LAST_VALUE_CH7_LSB[  
7:0]  
R
0b  
Next 8 bits of the last result for this analog input channel.  
8.6.100 RECENT_CH7_MSB Register (Address = 0xAF) [Reset = 0x0]  
RECENT_CH7_MSB is shown in Figure 8-116 and described in Table 8-112.  
Return to the Table 8-11.  
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Figure 8-116. RECENT_CH7_MSB Register  
7
6
5
4
3
2
1
0
LAST_VALUE_CH7_MSB[7:0]  
R-0b  
Table 8-112. RECENT_CH7_MSB Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
LAST_VALUE_CH7_MSB[ R  
7:0]  
0b  
MSB aligned first 8 bits of the last result for this analog input  
channel.  
8.6.101 GPO0_TRIG_EVENT_SEL Register (Address = 0xC3) [Reset = 0x2]  
GPO0_TRIG_EVENT_SEL is shown in Figure 8-117 and described in Table 8-113.  
Return to the Table 8-11.  
Figure 8-117. GPO0_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO0_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-113. GPO0_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO0_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO0.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO0 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO0 output.  
8.6.102 GPO1_TRIG_EVENT_SEL Register (Address = 0xC5) [Reset = 0x2]  
GPO1_TRIG_EVENT_SEL is shown in Figure 8-118 and described in Table 8-114.  
Return to the Table 8-11.  
Figure 8-118. GPO1_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO1_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-114. GPO1_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO1_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO1.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO1 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO1 output.  
8.6.103 GPO2_TRIG_EVENT_SEL Register (Address = 0xC7) [Reset = 0x2]  
GPO2_TRIG_EVENT_SEL is shown in Figure 8-119 and described in Table 8-115.  
Return to the Table 8-11.  
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Figure 8-119. GPO2_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO2_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-115. GPO2_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO2_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO2.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO2 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO2 output.  
8.6.104 GPO3_TRIG_EVENT_SEL Register (Address = 0xC9) [Reset = 0x2]  
GPO3_TRIG_EVENT_SEL is shown in Figure 8-120 and described in Table 8-116.  
Return to the Table 8-11.  
Figure 8-120. GPO3_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO3_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-116. GPO3_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO3_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO3.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO3 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO3 output.  
8.6.105 GPO4_TRIG_EVENT_SEL Register (Address = 0xCB) [Reset = 0x2]  
GPO4_TRIG_EVENT_SEL is shown in Figure 8-121 and described in Table 8-117.  
Return to the Table 8-11.  
Figure 8-121. GPO4_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO4_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-117. GPO4_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO4_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO4.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO4 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO4 output.  
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8.6.106 GPO5_TRIG_EVENT_SEL Register (Address = 0xCD) [Reset = 0x2]  
GPO5_TRIG_EVENT_SEL is shown in Figure 8-122 and described in Table 8-118.  
Return to the Table 8-11.  
Figure 8-122. GPO5_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO0_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-118. GPO5_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO0_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO5.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO5 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO5 output.  
8.6.107 GPO6_TRIG_EVENT_SEL Register (Address = 0xCF) [Reset = 0x2]  
GPO6_TRIG_EVENT_SEL is shown in Figure 8-123 and described in Table 8-119.  
Return to the Table 8-11.  
Figure 8-123. GPO6_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO6_TRIG_EVENT_SEL[7:0]  
R/W-10b  
Table 8-119. GPO6_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO6_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO6.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO6 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO6 output.  
8.6.108 GPO7_TRIG_EVENT_SEL Register (Address = 0xD1) [Reset = 0x2]  
GPO7_TRIG_EVENT_SEL is shown in Figure 8-124 and described in Table 8-120.  
Return to the Table 8-11.  
Figure 8-124. GPO7_TRIG_EVENT_SEL Register  
7
6
5
4
3
2
1
0
GPO7_TRIG_EVENT_SEL[7:0]  
R/W-10b  
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Table 8-120. GPO7_TRIG_EVENT_SEL Register Field Descriptions  
Bit  
Field  
Type  
Reset  
Description  
7-0  
GPO7_TRIG_EVENT_SE R/W  
L[7:0]  
10b  
Select the inputs AIN/GPIO[7:0], analog or digital, which can trigger  
an event based update on GPO7.  
0b = Alert flags for the AIN/GPIO corresponding to this bit do not  
trigger GPO7 output.  
1b = Alert flags for the AIN/GPIO corresponding to this bit trigger  
GPO7 output.  
8.6.109 GPO_TRIGGER_CFG Register (Address = 0xE9) [Reset = 0x0]  
GPO_TRIGGER_CFG is shown in Figure 8-125 and described in Table 8-121.  
Return to the Table 8-11.  
Figure 8-125. GPO_TRIGGER_CFG Register  
7
6
5
4
3
2
1
0
GPO_TRIGGER_UPDATE_EN[7:0]  
R/W-0b  
Table 8-121. GPO_TRIGGER_CFG Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO_TRIGGER_UPDATE R/W  
_EN[7:0]  
0b  
Update digital outputs GPO[7:0] when corresponding trigger is set.  
0b = Digital output is not updated in response to alert flags.  
1b = Digital output is updated when corresponding alert flags are set.  
Configure GPOx_TRIG_EVENT_SEL register to select which alert  
flags can trigger an update on the desired GPO.  
8.6.110 GPO_VALUE_TRIG Register (Address = 0xEB) [Reset = 0x0]  
GPO_VALUE_TRIG is shown in Figure 8-126 and described in Table 8-122.  
Return to the Table 8-11.  
Figure 8-126. GPO_VALUE_TRIG Register  
7
6
5
4
3
2
1
0
GPO_VALUE_ON_TRIGGER[7:0]  
R/W-0b  
Table 8-122. GPO_VALUE_TRIG Register Field Descriptions  
Bit  
7-0  
Field  
Type  
Reset  
Description  
GPO_VALUE_ON_TRIGG R/W  
ER[7:0]  
0b  
Value to be set on digital outputs GPO[7:0] when corresponding  
trigger occurs. GPO update on alert flags must be enabled in  
corresponding bit in GPO_TRIGGER_CFG register.  
0b = Digital output set to logic 0.  
1b = Digital output set to logic 1.  
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9 Application and Implementation  
Note  
Information in the following applications sections is not part of the TI component specification, and TI  
does not warrant its accuracy or completeness. TI’s customers are responsible for determining  
suitability of components for their purposes. Customers should validate and test their design  
implementation to confirm system functionality.  
9.1 Application Information  
The following sections give example circuits and suggestions for using the ADS7128-Q1 in various applications.  
9.2 Typical Applications  
9.2.1 Mixed-Channel Configuration  
AVDD (VREF  
)
Digital Output (open-drain)  
Digital Output (push-pull)  
Analog Input  
Analog Input  
Analog Input  
Analog Input  
I2C  
Controller  
Device  
Digital Input  
Digital Input  
Figure 9-1. DAQ Circuit: Single-Supply DAQ  
9.2.1.1 Design Requirements  
The goal of this application is to configure some channels of the ADS7138-Q1 as digital inputs, open-drain digital  
outputs, and push-pull digital outputs.  
9.2.1.2 Detailed Design Procedure  
The ADS7138-Q1 can support GPIO functionality at each input pin. Any analog input pin can be independently  
configured as a digital input, a digital open-drain output, or a digital push-pull output though the PIN_CFG and  
GPIO_CFG registers; see Table 8-5.  
9.2.1.2.1 Digital Input  
The digital input functionality can be used to monitor a signal within the system. Figure 9-2 shows that the state  
of the digital input can be read from the GPI_VALUE register.  
ADC  
From input device  
GPIx  
GPIx  
SW  
AVDD  
Figure 9-2. Digital Input  
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9.2.1.2.2 Digital Open-Drain Output  
The channels of the ADS7138-Q1 can be configured as digital open-drain outputs supporting an output voltage  
up to 5.5 V. An open-drain output, as shown in Figure 9-3, consists of an internal FET (Q) connected to ground.  
The output is idle when not driven by the device, which means Q is off and the pullup resistor, R PULL_UP  
,
connects the GPOx node to the desired output voltage. The output voltage can range anywhere up to 5.5 V,  
depending on the external voltage that the GPIOx is pulled up to. When the device is driving the output, Q turns  
on, thus connecting the pullup resistor to ground and bringing the node voltage at GPOx low.  
VPULL_UP  
Receiving Device  
ADC  
RPULL_UP  
GPOx  
ILOAD  
Q
Figure 9-3. Digital Open-Drain Output  
The minimum value of the pullup resistor, as calculated in Equation 3, is given by the ratio of VPULL_UP and the  
maximum current supported by the device digital output (5 mA).  
RMIN = (VPULL_UP / 5 mA)  
(3)  
The maximum value of the pullup resistor, as calculated in Equation 4, depends on the minimum input current  
requirement, ILOAD, of the receiving device driven by this GPIO.  
RMAX = (VPULL_UP / ILOAD  
)
(4)  
Select RPULL_UP such that RMIN < RPULL_UP < RMAX  
.
9.2.1.3 Application Curve  
60000  
45000  
39581  
30000  
15000  
0
25955  
2048  
2049  
Output Code  
C001  
Standard deviation = 0.49 LSB  
Figure 9-4. DC Input Histogram  
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9.2.2 Digital Push-Pull Output  
The channels of the ADS7138-Q1 can be configured as digital push-pull outputs supporting an output voltage up  
to AVDD. As shown in Figure 9-5, a push-pull output consists of two mirrored opposite bipolar transistors, Q1  
and Q2. The device can both source and sink current because only one transistor is on at a time (either Q2 is on  
and pulls the output low, or Q1 is on and sets the output high). A push-pull configuration always drives the line  
opposed to an open-drain output where the line is left floating.  
ADC  
AVDD  
Q1  
GPOx  
Digital  
output  
Q2  
Figure 9-5. Digital Push-Pull Output  
10 Power Supply Recommendations  
10.1 AVDD and DVDD Supply Recommendations  
The ADS7138-Q1 has two separate power supplies: AVDD and DVDD. The device operates on AVDD; DVDD is  
used for the interface circuits. For supplies greater than 2.35 V, AVDD and DVDD can be shorted externally if  
single-supply operation is desired. The AVDD supply also defines the full-scale input range of the device.  
Decouple the AVDD and DVDD pins individually, as shown in Figure 10-1, with 1-µF ceramic decoupling  
capacitors. The minimum capacitor value required for AVDD and DVDD is 200 nF and 20 nF, respectively. If both  
supplies are powered from the same source, a minimum capacitor value of 220 nF is required for decoupling.  
Connect a 1-µF decoupling capacitor between the DECAP and GND pins for the internal power supply.  
AVDD  
AVDD  
1 mF  
DECAP  
1 mF  
GND  
GND  
1 mF  
DVDD  
DVDD  
Figure 10-1. Power-Supply Decoupling  
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11 Layout  
11.1 Layout Guidelines  
Figure 11-1 shows a board layout example for the ADS7138-Q1. Avoid crossing digital lines with the analog  
signal path and keep the analog input signals and the AVDD supply away from noise sources.  
Use 1-µF ceramic bypass capacitors in close proximity to the analog (AVDD) and digital (DVDD) power-supply  
pins. Avoid placing vias between the AVDD and DVDD pins and the bypass capacitors. Connect the GND pin to  
the ground plane using short, low-impedance paths. The AVDD supply voltage also functions as the reference  
voltage for the ADS7138-Q1. Place the decoupling capacitor for AVDD close to the device AVDD and GND pins  
and connect the decoupling capacitor to the device pins with thick copper tracks.  
11.2 Layout Example  
ALERT  
DECAP  
AVDD  
SCL  
SDA  
AIN/GPIO  
Figure 11-1. Example Layout  
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12 Device and Documentation Support  
12.1 Receiving Notification of Documentation Updates  
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on  
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For  
change details, review the revision history included in any revised document.  
12.2 Support Resources  
TI E2Esupport forums are an engineer's go-to source for fast, verified answers and design help — straight  
from the experts. Search existing answers or ask your own question to get the quick design help you need.  
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do  
not necessarily reflect TI's views; see TI's Terms of Use.  
12.3 Trademarks  
TI E2Eis a trademark of Texas Instruments.  
All trademarks are the property of their respective owners.  
12.4 Electrostatic Discharge Caution  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled  
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may  
be more susceptible to damage because very small parametric changes could cause the device not to meet its published  
specifications.  
12.5 Glossary  
TI Glossary  
This glossary lists and explains terms, acronyms, and definitions.  
13 Mechanical, Packaging, and Orderable Information  
The following pages include mechanical, packaging, and orderable information. This information is the most  
current data available for the designated devices. This data is subject to change without notice and revision of  
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.  
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SBAS977A – MAY 2020 – REVISED OCTOBER 2020  
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PACKAGE OUTLINE  
RTE0016C  
WQFN - 0.8 mm max height  
S
C
A
L
E
3
.
6
0
0
PLASTIC QUAD FLATPACK - NO LEAD  
3.1  
2.9  
B
A
PIN 1 INDEX AREA  
3.1  
2.9  
C
0.8 MAX  
SEATING PLANE  
0.08  
0.05  
0.00  
1.68 0.07  
(0.1) TYP  
5
8
EXPOSED  
THERMAL PAD  
12X 0.5  
4
9
4X  
SYMM  
17  
1.5  
1
12  
0.30  
16X  
0.18  
PIN 1 ID  
(OPTIONAL)  
16  
13  
0.1  
C A B  
SYMM  
0.05  
0.5  
0.3  
16X  
4219117/A 09/2016  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.  
www.ti.com  
Copyright © 2020 Texas Instruments Incorporated  
82  
Submit Document Feedback  
Product Folder Links: ADS7138-Q1  
ADS7138-Q1  
SBAS977A – MAY 2020 – REVISED OCTOBER 2020  
www.ti.com  
EXAMPLE BOARD LAYOUT  
RTE0016C  
WQFN - 0.8 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(
1.68)  
SYMM  
16  
13  
16X (0.6)  
1
12  
16X (0.24)  
SYMM  
(2.8)  
17  
(0.58)  
TYP  
12X (0.5)  
9
4
(
0.2) TYP  
VIA  
5
8
(R0.05)  
ALL PAD CORNERS  
(0.58) TYP  
(2.8)  
LAND PATTERN EXAMPLE  
SCALE:20X  
0.07 MIN  
ALL AROUND  
0.07 MAX  
ALL AROUND  
SOLDER MASK  
OPENING  
METAL  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
NON SOLDER MASK  
DEFINED  
(PREFERRED)  
SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
4219117/A 09/2016  
NOTES: (continued)  
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
number SLUA271 (www.ti.com/lit/slua271).  
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown  
on this view. It is recommended that vias under paste be filled, plugged or tented.  
www.ti.com  
Copyright © 2020 Texas Instruments Incorporated  
Submit Document Feedback  
83  
Product Folder Links: ADS7138-Q1  
ADS7138-Q1  
SBAS977A – MAY 2020 – REVISED OCTOBER 2020  
www.ti.com  
EXAMPLE STENCIL DESIGN  
RTE0016C  
WQFN - 0.8 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(
1.55)  
16  
13  
16X (0.6)  
1
12  
16X (0.24)  
17  
SYMM  
(2.8)  
12X (0.5)  
9
4
METAL  
ALL AROUND  
5
8
SYMM  
(2.8)  
(R0.05) TYP  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
EXPOSED PAD 17:  
85% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE  
SCALE:25X  
4219117/A 09/2016  
NOTES: (continued)  
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
www.ti.com  
Copyright © 2020 Texas Instruments Incorporated  
84  
Submit Document Feedback  
Product Folder Links: ADS7138-Q1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
ADS7138QRTERQ1  
ACTIVE  
WQFN  
RTE  
16  
3000 RoHS & Green  
NIPDAU  
Level-2-260C-1 YEAR  
-40 to 125  
7138Q  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
OTHER QUALIFIED VERSIONS OF ADS7138-Q1 :  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
Catalog: ADS7138  
NOTE: Qualified Version Definitions:  
Catalog - TI's standard catalog product  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
6-Nov-2020  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
ADS7138QRTERQ1  
WQFN  
RTE  
16  
3000  
330.0  
12.4  
3.3  
3.3  
1.1  
8.0  
12.0  
Q2  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
6-Nov-2020  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
WQFN RTE 16  
SPQ  
Length (mm) Width (mm) Height (mm)  
367.0 367.0 35.0  
ADS7138QRTERQ1  
3000  
Pack Materials-Page 2  
PACKAGE OUTLINE  
RTE0016K  
WQFN - 0.8 mm max height  
S
C
A
L
E
3
.
6
0
0
PLASTIC QUAD FLATPACK - NO LEAD  
3.15  
2.85  
B
A
PIN 1 INDEX AREA  
3.15  
2.85  
0.1 MIN  
(0.13)  
A
-
A
4
0
.
0
0
0
SECTION A-A  
TYPICAL  
0.8  
0.7  
C
SEATING PLANE  
0.08  
0.05  
0.00  
1.66 0.1  
(0.2) TYP  
EXPOSED  
THERMAL PAD  
5
8
12X 0.5  
4
9
(0.16)  
TYP  
4X  
SYMM  
A
A
17  
1.5  
1
12  
0.30  
0.18  
16X  
PIN 1 ID  
(OPTIONAL)  
13  
16  
0.1  
C A B  
SYMM  
0.05  
0.5  
0.3  
16X  
4224938/B 06/2019  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
RTE0016K  
WQFN - 0.8 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(
1.66)  
SYMM  
13  
16  
16X (0.6)  
1
12  
16X (0.24)  
SYMM  
(2.8)  
17  
(0.58)  
TYP  
12X (0.5)  
9
4
(
0.2) TYP  
VIA  
5
8
(R0.05)  
ALL PAD CORNERS  
(0.58) TYP  
(2.8)  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:20X  
0.07 MIN  
ALL AROUND  
0.07 MAX  
ALL AROUND  
SOLDER MASK  
OPENING  
METAL  
EXPOSED  
METAL  
EXPOSED  
METAL  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
NON SOLDER MASK  
SOLDER MASK  
DEFINED  
DEFINED  
(PREFERRED)  
SOLDER MASK DETAILS  
4224938/B 06/2019  
NOTES: (continued)  
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
number SLUA271 (www.ti.com/lit/slua271).  
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown  
on this view. It is recommended that vias under paste be filled, plugged or tented.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
RTE0016K  
WQFN - 0.8 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(
1.51)  
16  
13  
16X (0.6)  
1
12  
16X (0.24)  
17  
SYMM  
(2.8)  
12X (0.5)  
9
4
METAL  
ALL AROUND  
5
8
SYMM  
(2.8)  
(R0.05) TYP  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
EXPOSED PAD 17:  
84% PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE  
SCALE:25X  
4224938/B 06/2019  
NOTES: (continued)  
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
www.ti.com  
IMPORTANT NOTICE AND DISCLAIMER  
TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE  
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY  
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD  
PARTY INTELLECTUAL PROPERTY RIGHTS.  
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate  
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable  
standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you  
permission to use these resources only for development of an application that uses the TI products described in the resource. Other  
reproduction and display of these resources is prohibited. No license is granted to any other TI intellectual property right or to any third  
party intellectual property right. TI disclaims responsibility for, and you will fully indemnify TI and its representatives against, any claims,  
damages, costs, losses, and liabilities arising out of your use of these resources.  
TI’s products are provided subject to TI’s Terms of Sale (www.ti.com/legal/termsofsale.html) or other applicable terms available either on  
ti.com or provided in conjunction with such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable  
warranties or warranty disclaimers for TI products.  
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2020, Texas Instruments Incorporated  

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