ADT7320UCPZ-RL7 [ADI]
±0.25°C Accurate, 16-Bit Digital SPI Temperature Sensor; ±0.25 ° C精度， 16位数字SPI温度传感器
| 型号： | ADT7320UCPZ-RL7 |
| 厂家： | 
ADI |
| 描述： | ±0.25°C Accurate, 16-Bit Digital SPI Temperature Sensor |
| 文件： | 总24页 (文件大小：266K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
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DT73.±
FEATURES
GENERAL DESCRIPTION
Temperature accuracy 0.2ꢀ°C from −20°C to +10ꢀ°C
13- or 16-bit user-selectable temperature-to-digital
converter
The ADT7320 is a high accuracy digital temperature sensor
offering breakthrough performance over a wide industrial range,
housed in an LFCSP package. It contains a band gap temperature
reference and a 13-bit analog-to-digital converter (ADC) to
monitor and digitize the temperature to a 0.0625°C resolution.
The ADC resolution, by default, is set to 13 bits (0.0625°C).
This can be changed to 16 bits (0.0078°C) by setting Bit 7 in the
configuration register (Register Address 0x01).
Low drift silicon temperature sensor
No temperature calibration/correction required by user
Power saving 1 sample per second (SPS) mode
Fast first conversion on power-up of 6 ms
SPI-compatible interface
Operating temperature from −40°C to +1ꢀ0°C
Operating voltage: 2.7 V to ꢀ.ꢀ V
The ADT7320 is guaranteed to operate over supply voltages from
2.7 V to 5.5 V. Operating at 3.3 V, the average supply current is
typically 210 μA. The ADT7320 has a shutdown mode that
powers down the device and offers a shutdown current of
typically 2 μA. The ADT7320 is rated for operation over the
−40°C to +150°C temperature range.
Critical overtemperature indicator
Programmable overtemperature/undertemperature interrupt
Low power consumption: 700 μW typical at 3.3 V
Shutdown mode for lower power: 7 μW typical at 3.3 V
16-lead RoHS-compliant LFCSP package
APPLICATIONS
The CT pin is an open-drain output that becomes active when
the temperature exceeds a programmable critical temperature
limit. The default critical temperature limit is 147°C. The INT
pin is also an open-drain output that becomes active when the
temperature exceeds a programmable limit. The INT and CT
pins can operate in either comparator or interrupt mode.
RTD and thermistor replacement
Medical equipment
Cold junction compensation
Industrial controls and test
Food transportation and storage
Environmental monitoring and HVAC
FUNCTIONAL BLOCK DIAGRAM
1
2
3
4
SCLK
DOUT
ADT7320
INTERNAL
OSCILLATOR
INTERNAL
REFERENCE
DIN
CS
6
5
CT
T
T
T
CRIT
HIGH
LOW
Σ-Δ
MODULATOR
TEMPERATURE
SENSOR
TEMPERATURE
VALUE
CONFIGURATION
AND STATUS
REGISTERS
INT
REGISTER
T
T
HYST
REGISTER
CRIT
REGISTER
FILTER
LOGIC
7
8
GND
T
T
HIGH
REGISTER
LOW
REGISTER
V
DD
Figure 1.
Rev. PrA
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2010 Analog Devices, Inc. All rights reserved.
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T -LECOFC°ONTENTSC
Features .............................................................................................. 1
Status Register............................................................................. 14
Configuration Register .............................................................. 15
Temperature Value Register...................................................... 16
ID Register................................................................................... 16
TCRIT Setpoint Register ............................................................... 16
THYST Setpoint Register............................................................... 17
THIGH Setpoint Register .............................................................. 17
TLOW Setpoint Register ............................................................... 17
Serial Interface ................................................................................ 18
SPI Command Byte.................................................................... 18
Writing Data ............................................................................... 19
Reading Data............................................................................... 20
Interfacing to DSPs or Microcontrollers................................. 20
Serial Interface Reset.................................................................. 20
INT and CT Outputs...................................................................... 21
Undertemperature and Overtemperature Detection ............ 21
Applications Information.............................................................. 23
Thermal Response Time ........................................................... 23
Supply Decoupling ..................................................................... 23
Temperature Monitoring........................................................... 23
Outline Dimensions....................................................................... 24
Ordering Guide .......................................................................... 24
Applications....................................................................................... 1
General Description......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
SPI Timing Specifications ........................................................... 4
Absolute Maximum Ratings............................................................ 5
ESD Caution.................................................................................. 5
Pin Configuration and Function Descriptions............................. 6
Typical Performance Characteristics ............................................. 7
Theory of Operation ........................................................................ 9
Circuit Information...................................................................... 9
Converter Details.......................................................................... 9
Temperature Measurement ......................................................... 9
One-Shot Mode .......................................................................... 10
1 SPS Mode.................................................................................. 10
Continuous Read Mode............................................................. 12
Shutdown..................................................................................... 12
Fault Queue ................................................................................. 12
Temperature Data Format......................................................... 13
Temperature Conversion Formulas ......................................... 13
Registers........................................................................................... 14
REVISION HISTORY
6/10—Revision PrA: Preliminary Version
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DT73.±
SPE°IFI° TIONSC
TA = −40°C to +125°C, VDD = 2.7 V to 5.5 V, unless otherwise noted.
Table 1.
Parameter
Min
Typ
Max
Unit Test Conditions/Comments
TEMPERATURE SENSOR AND ADC
Accuracy1
±±.2±2 °C
TA = −1±°C to +85°C, VDD = 3.± V
±±.25
±±.5±
°C
°C
TA = −2±°C to +1±5°C, VDD = 2.7 V to 3.3 V
TA = −4±°C to +125°C, VDD = 2.7 V to 3.3 V
TA = −1±°C to +1±5°C, VDD = 4.5 V to 5.5 V
TA = −4±°C to +125°C, VDD = 4.5 V to 5.5 V
TA = 125°C to 15±°C, VDD = 4.5 V to 5.5 V
TA = 125°C to 15±°C, VDD = 2.7 V to 3.3 V
±±.5±3 °C
±±.75
°C
°C
°C
−±.85
−1.±
13
ADC Resolution
Bits
Twos complement temperature value of sign bit plus 12 ADC
bits (power-up default resolution)
16
Bits
Twos complement temperature value of sign bit plus 15 ADC
bits (Bit 7 = 1 in the configuration register)
Temperature Resolution
13 Bit
16 Bit
±.±625
±.±±78
24±
6
6±
±.±2
±±.±15
±.±±73
±.1
°C
°C
ms
ms
ms
°C
13-bit resolution (sign + 12 bit)
16-bit resolution (sign + 15 bit)
Temperature Conversion Time
Fast Temperature Conversion Time
1 SPS Conversion Time
Temperature Hysteresis
Repeatability4
Continuous conversion and one-shot conversion mode
First conversion on power-up only
Conversion time for 1 SPS mode
Temperature cycle = 25°C to 125°C and back to 25°C
TA = 25°C
°C
°C
Drift5
5±± hour stress test at 15±°C with VDD = 5.± V
DC PSRR
°C/V TA = 25°C
DIGITAL OUTPUTS (OPEN DRAIN)
High Output Leakage Current, IOH
Output High Current
Output Low Voltage, VOL
Output High Voltage, VOH
Output Capacitance, COUT
DIGITAL INPUTS
±.1
5
1
±.4
μA
mA
V
V
pF
CT and INT pins pulled up to 5.5 V
VOH = 5.5 V
IOL = 2 mA @ 5.5 V, IOL = 1 mA @ 3.3 V
±.7 × VDD
3
Input Current
±1
±.4
μA
V
V
VIN = ± V to VDD
Input Low Voltage, VIL
Input High Voltage, VIH
Pin Capacitance
±.7 × VDD
VOH − ±.3
5
1±
pF
DIGITAL OUTPUT (DOUT)
Output High Voltage, VOH
Output Low Voltage, VOL
Output Capacitance, COUT
POWER REQUIREMENTS
Supply Voltage
V
V
pF
ISOURCE = ISINK = 2±± μA
IOL = 2±± μA
±.4
5±
2.7
5.5
V
Supply Current
At 3.3 V
At 5.5 V
21±
23±
25±
3±±
μA
μA
Peak current while converting, SPI interface inactive
Peak current while converting, SPI interface inactive
1 SPS Current
At 3.3 V
At 5.5 V
46
65
μA
μA
VDD = 3.3 V, 1 SPS mode, TA = 25°C
VDD = 5.5 V, 1 SPS mode, TA = 25°C
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Shutdown Current
At 3.3 V
At 5.5 V
Power Dissipation Normal Mode
Power Dissipation 1 SPS
2.±
4.4
7±±
15±
15
25
μA
μA
μW
μW
Supply current in shutdown mode
Supply current in shutdown mode
VDD = 3.3 V, normal mode at 25°C
Power dissipated forVDD = 3.3 V, TA = 25°C
1 Accuracy includes repeatability.
2 The equivalent three-sigma limits are ±±.15°C. This three-sigma specification is provided to enable comparison with other vendors who use these limits.
3 For higher accuracy at 5 V operation, contact an Analog Devices, Inc., sales representative.
4 Based on a floating average of 1± readings.
5 Drift includes solder heat resistance (SHR) and lifetime tests performed as per JEDEC Standard JESD22-A1±8.
SPI TIMING SPECIFICATIONS
TA = −40°C to +150°C, VDD = 2.7 V to 5.5 V, unless otherwise noted. All input signals are specified with rise time (tR) = fall time (tF) = 5 ns
(10% to 90% of VDD) and timed from a voltage level of 1.6 V.
Table 2.
Parameter1, 2
Limit at TMIN, TMAX (B Version)
Unit
Conditions/Comments
CS falling edge to SCLK active edge setup time3
t1
t2
t3
t4
t5
t6
±
ns min
ns min
ns min
ns min
ns min
ns min
ns max
ns max
ns min
ns max
ns min
ns min
ns max
ns max
ns min
1±±
1±±
3±
25
±
6±
8±
1±
8±
±
SCLK high pulse width
SCLK low pulse width
Data valid to SCLK edge setup time
Data valid to SCLK edge hold time
SCLK active edge to data valid delay3
VDD = 4.5 V to 5.5 V
VDD = 2.7 V to 3.6 V
Bus relinquish time after CS inactive edge
4
t7
t8
t9
CS rising edge to SCLK edge hold time
CS falling edge to DOUT active time
VDD = 4.5 V to 5.5 V
VDD = 2.7 V to 3.6 V
SCLK inactive edge to DOUT high
±
6±
8±
1±
t1±
1 Sample tested during initial release to ensure compliance. All input signals are specified with tR = tF = 5 ns (1±% to 9±% of VDD) and timed from a voltage level of 1.6 V.
2 See Figure 2.
3 SCLK active edge is falling edge of SCLK.
4 This means that the times quoted in the timing characteristics are the true bus relinquish times of the part and, as such, are independent of external bus loading
capacitances.
CS
t1
t2
1
t8
8
t3
7
7
2
3
8
1
2
SCLK
DIN
t4
t5
MSB
LSB
t10
t6
t7
t9
DOUT
LSB
MSB
Figure 2. Detailed SPI Timing Diagram
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-SOLUTECM XIMUMCR TINGSC
Table 3.
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Parameter
Rating
VDD to GND
DIN Input Voltage to GND
DOUT Voltage to GND
−±.3 V to +7 V
−±.3 V to VDD + ±.3 V
−±.3 V to VDD + ±.3 V
−±.3 V to VDD + ±.3 V
−±.3 V to VDD + ±.3 V
−±.3 V to VDD + ±.3 V
2.± kV
−4±°C to +15±°C
−65°C to +16±°C
15±°C
SCLK Input Voltage to GND
CS Input Voltage to GND
CT and INT Output Voltage to GND
ESD Rating (Human Body Model)
Operating Temperature Range
Storage Temperature Range
Maximum Junction Temperature, TJMAX
16-Lead LFCSP
ESD CAUTION
Power Dissipation1
Thermal Impedance3
WMAX = (TJMAX − TA )/θJA
2
θJA, Junction-to-Ambient (Still Air)
θJC, Junction-to-Case
121°C/W
56°C/W
IR Reflow Soldering
22±°C
Peak Temperature (RoHS-
Compliant Package)
26±°C (±°C)
Time at Peak Temperature
Ramp-Up Rate
Ramp-Down Rate
2± sec to 4± sec
3°C/sec maximum
−6°C/sec maximum
8 minutes maximum
Time from 25°C to Peak Temperature
1 Values relate to package being used on a standard 2-layer PCB. This gives a
worst-case θJA and θJC
.
2 TA = ambient temperature.
3 Junction-to-case resistance is applicable to components featuring a
preferential flow direction, for example, components mounted on a heat
sink. Junction-to-ambient is more useful for air-cooled, PCB-mounted
components.
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PINC°ONFIGUR TIONC NDCFUN°TIONCDES°RIPTIONSC
SCLK 1
12
V
DD
ADT7320
TOP VIEW
(Not to Scale)
2
3
4
11 GND
10 CT
DOUT
DIN
9
INT
CS
NOTES
1. NC = NO CONNECT.
2. THE EXPOSED PADDLE IS CONNECTED INTERNALLY.
FOR INCREASED RELIABILITY OF THE SOLDER
JOINTS AND MAXIMUM THERMAL CAPABILITY, IT IS
RECOMMENDED THAT THE PAD BE SOLDERED TO
THE GROUND PLANE.
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
SCLK
Serial Clock Input. The serial clock is used to clock in and clock out data to and from any register of the
ADT732±.
2
3
DOUT
DIN
Serial Data Output. Data is clocked out on the SCLK falling edge and is valid on the SCLK rising edge.
Serial Data Input. Serial data to be loaded to the control registers of the part is provided on this input. Data
is clocked into the registers on the rising edge of SCLK.
4
5
6
7
8
9
CS
Chip Select Input. The device is selected when this input is low. The device is disabled when this pin is high.
NC
NC
NC
NC
INT
No Connect.
No Connect.
No Connect.
No Connect.
Overtemperature and Undertemperature Indicator. Logic output. Power-up default setting is as an active
low comparator interrupt. Open-drain configuration. A pull-up resistor is required, typically 1± kΩ.
1±
CT
Critical Overtemperature Indicator. Logic output. Power-up default polarity is active low. Open-drain
configuration. A pull-up resistor is required, typically 1± kΩ.
11
12
GND
VDD
Analog and Digital Ground.
Positive Supply Voltage (2.7 V to 5.5 V). The supply should be decoupled with a ±.1 μF ceramic capacitor to
ground.
13
14
15
16
NC
NC
NC
NC
No Connect.
No Connect.
No Connect.
No Connect.
EPAD
The exposed paddle is connected internally. For increased reliability of the solder joints and maximum
thermal capability, it is recommended that the pad be soldered to the ground plane.
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TYPI° LCPERFORM N°EC°H R °TERISTI°SC
0.30
0.25
0.20
0.15
0.10
0.05
0
1.0
5.5V CONTINUOUS
CONVERSION
0.5
0
3.0V CONTINUOUS
CONVERSION
5.5V 1SPS
3.0V 1SPS
50
–0.5
–1.0
–100
–50
0
100
150
200
–50
–30
–10
10
30
50
70
90
110
130
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 4. Temperature Accuracy at 3 V
Figure 6. Operating Supply Current vs. Temperature
1.0
6
5
4
3
2
1
0
0.5
0
5.5V
5.0V
4.5V
3.6V
–0.5
3.0V
2.7V
–1.0
–100
–50
0
50
100
150
200
–50
–30
–10
10
30
50
70
90
110
130
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 5. Temperature Accuracy at 5 V
Figure 7. Shutdown Current vs. Temperature
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0.30
0.25
0.20
0.15
0.10
0.05
160
140
120
100
80
I
CONTINUOUS CONVERSION
DD
60
40
I
1SPS
DD
20
0
2.5
0
3.0
3.5
4.0
4.5
5.0
5.5
6.0
0
5
10
15
20
25
30
35
40
SUPPLY VOLTAGE (V)
TIME (Seconds)
Figure 8. Average Operating Supply Current vs. Supply Voltage at 25°C
Figure 10. Response to Thermal Shock
8
7
6
5
4
3
2
1
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
SUPPLY VOLTAGE (V)
Figure 9. Shutdown Current vs. Supply Voltage at 25°C
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DT73.±
THEORYCOFCOPER TIONC
CIRCUIT INFORMATION
Σ-Δ MODULATOR
INTEGRATOR
The ADT7320 is a 13-bit digital temperature sensor that is
extendable to 16 bits for greater resolution. An on-board
temperature sensor generates a voltage proportional to absolute
temperature, which is compared to an internal voltage reference
and input to a precision digital modulator.
COMPARATOR
VOLTAGE REF
AND VPTAT
1-BIT
DAC
The on-board temperature sensor has excellent accuracy and
linearity over the entire rated temperature range without
needing correction or calibration by the user.
1-BIT
TEMPERATURE
VALUE
REGISTER
CLOCK
LPF DIGITAL
FILTER
GENERATOR
The sensor output is digitized by a Σ-Δ modulator, also known
as the charge balance type ADC. This type of converter uses
time-domain oversampling and a high accuracy comparator to
deliver 16 bits of resolution in an extremely compact circuit.
13-BIT
Figure 11. Σ-∆ Modulator
TEMPERATURE MEASUREMENT
In normal mode, the ADT7320 runs an automatic conversion
sequence. During this automatic conversion sequence, a
conversion takes 240 ms to complete and the ADT7320 is
continuously converting. This means that as soon as one
temperature conversion is completed, another temperature
conversion begins. Each temperature conversion result is
stored in the temperature value register and is available
through the SPI interface. In continuous conversion mode,
the read operation provides the most recent converted result.
Configuration register functions consist of the following:
•
•
•
Switching between 13-bit and 16-bit resolution
Switching between normal operation and full power-down
Switching between comparator and interrupt event modes
on the INT and CT pins
•
•
•
Setting the active polarity of the CT and INT pins
Setting the number of faults that activate CT and INT
Enabling the standard one-shot mode and 1 SPS mode
At power-up, the first conversion is a fast conversion, taking
typically 6 ms. If the temperature exceeds 147°C, the CT pin
asserts low. If the temperature exceeds 64°C, the INT pin asserts
low. Fast conversion temperature accuracy is typically within 5°C.
CONVERTER DETAILS
The Σ-ꢀ modulator consists of an input sampler, a summing
network, an integrator, a comparator, and a 1-bit DAC. This
architecture creates a negative feedback loop and minimizes the
integrator output by changing the duty cycle of the comparator
output in response to the input voltage changes. The comparator
samples the output of the integrator at a much higher rate than
the input sampling frequency. This oversampling spreads the
quantization noise over a much wider band than that of the input
signal, improving overall noise performance and increasing
accuracy.
The conversion clock for the part is generated internally. No
external clock is required except when reading from and writing
to the serial port.
The measured temperature value is compared with a critical
temperature limit (stored in the 16-bit TCRIT setpoint read/write
register), a high temperature limit (stored in the 16-bit THIGH
setpoint read/write register), and a low temperature limit (stored
in the 16-bit TLOW setpoint read/write register). If the measured
value exceeds these limits, the INT pin is activated; and if it exceeds
the TCRIT limit, the CT pin is activated. The INT and CT pins are
programmable for polarity via the configuration register, and
the INT and CT pins are also programmable for interrupt mode
via the configuration register.
The modulated output of the comparator is encoded using a
circuit technique that results in SPI temperature data.
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CS
0x08
0x20
DIN
WAIT 240ms MINIMUM
FOR CONVERSION TO FINISH
DATA
DOUT
SCLK
Figure 12. Typical SPI One-Shot Write to Configuration Register Followed by a Read from the Temperature Value Register
ONE-SHOT MODE
1 SPS MODE
Setting Bit 5 to 0 and Bit 6 to 1 of the configuration register
(Register Address 0x01) enables the one-shot mode. When
this mode is enabled, the ADT7320 immediately completes a
conversion and then goes into shutdown mode.
In this mode, the part performs one measurement per second.
A conversion takes only 60 ms, and it remains in the idle state
for the remaining 940 ms period. This mode is enabled by
writing 1 to Bit 5 and 0 to Bit 6 of the configuration register
(Register Address 0x01).
Wait for a minimum of 240 ms after writing to the one-shot
bits before reading back the temperature from the temperature
value register. This time ensures that the ADT7320 has time to
power up and complete a conversion.
The one-shot mode is useful when one of the circuit design
priorities is to reduce power consumption.
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For the CT pin in the comparator mode, if the temperature drops
below the TCRIT − THYST value, a write to the one-shot bits (Bit 5
and Bit 6 of the configuration register, Register Address 0x01)
resets the CT pin, see Figure 13.
CT and INT Operation in One-Shot Mode
See Figure 13 for more information on one-shot CT pin
operation for TCRIT overtemperature events when one of the
limits is exceeded. Note that in interrupt mode, a read from
any register resets the INT and CT pins.
Note that when using one-shot mode, ensure that the refresh
rate is appropriate to the application being used.
For the INT pin in comparator mode, if the temperature drops
below the THIGH − THYST value or goes above the TLOW + THYST
value, a write to the one-shot bits (Bit 5 and Bit 6 of the
configuration register, Register Address 0x01) resets the INT pin.
TEMPERATURE
149°C
148°C
147°C
146°C
145°C
144°C
143°C
142°C
141°C
140°C
T
CRIT
T
– T
HYST
CRIT
CT PIN
POLARITY = ACTIVE LOW
CT PIN
POLARITY = ACTIVE HIGH
TIME
WRITE TO
WRITE TO
WRITE TO
BIT 5 AND BIT 6 OF BIT 5 AND BIT 6 OF BIT 5 AND BIT 6 OF
CONFIGURATION
REGISTER.*
CONFIGURATION
REGISTER.*
CONFIGURATION
REGISTER.*
*THERE IS A 240ms DELAY BETWEEN WRITING TO THE CONFIGURATION REGISTER TO START
A STANDARD ONE-SHOT CONVERSION AND THE CT PIN GOING ACTIVE. THIS IS DUE TO THE
CONVERSION TIME. THE DELAY IS 60ms IN THE CASE OF A ONE-SHOT CONVERSION.
Figure 13. One-Shot CT Pin
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SHUTDOWN
CONTINUOUS READ MODE
The ADT7320 can be placed in shutdown mode by writing 1
to Bit 5 and 1 to Bit 6 of the configuration register (Register
Address 0x01). The ADT7320 can be taken out of shutdown
mode by writing 0 to Bit 5 and 0 to Bit 6 of the configuration
register (Register Address 0x01). The ADT7320 typically takes
1 ms (with a 0.1 μF decoupling capacitor) to come out of shut-
down mode. The conversion result from the last conversion
prior to shutdown can still be read from the ADT7320 even
when it is in shutdown mode. When the part is taken out of
shutdown mode, the internal clock starts and a conversion initiates.
When the command byte = 01010100 (0x54), the contents of
the temperature value register can be read out without requiring
repeated writes to the communications register. By sending 16
SCLK clocks to the ADT7320, the contents of the temperature
value register are output onto the DOUT pin.
To exit the continuous read mode, the command byte 01010000
(0x50) must be written to the ADT7320.
While in continuous read mode, the part monitors activity
on the DIN line so that it can receive the instruction to exit
the continuous read mode. Additionally, a reset occurs if 32
consecutive 1s are seen on the DIN pin. Therefore, hold DIN
low in continuous read mode until an instruction is to be
written to the device.
FAULT QUEUE
Bit 0 and Bit 1 of the configuration register (Register Address 0x01)
are used to set up a fault queue. Up to four faults are provided to
prevent false tripping of the INT and CT pins when the ADT7320
is used in a noisy temperature environment. The number of
faults set in the queue must occur consecutively to set the INT
and CT outputs. For example, if the number of faults set in the
queue is four, then four consecutive temperature conversions
must occur, with each result exceeding a temperature limit in
any of the limit registers, before the INT and CT pins are activated.
If two consecutive temperature conversions exceed a temperature
limit and the third conversion does not, the fault count is reset to 0.
In continuous read mode, the temperature value register cannot
be read when a conversion is taking place. If an attempt is made
to read the temperature value register while a conversion is taking
place, then all 0s are read. This is because the continuous read
mode blocks read access to the temperature value register during a
conversion.
CS
0x54
DIN
TEMPERATURE
VALUE
TEMPERATURE
VALUE
TEMPERATURE
VALUE
DOUT
SCLK
Figure 14. Continuous Read Mode
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DT73.±
TEMPERATURE DATA FORMAT
TEMPERATURE CONVERSION FORMULAS
16-Bit Temperature Data Format
One LSB of the ADC corresponds to 0.0625°C in 13-bit mode.
The ADC can theoretically measure a temperature range of 255°C,
but the ADT7320 is guaranteed to measure a low value temperature
limit of −40°C to a high value temperature limit of +150°C. The
temperature measurement result is stored in the 16-bit temperature
value register and is compared with the high temperature limits
stored in the TCRIT setpoint register and the THIGH setpoint register. It
is also compared with the low temperature limit stored in the TLOW
setpoint register.
Positive Temperature = ADC Code(dec)/128
Negative Temperature = (ADC Code(dec) − 65,536)/128
where ADC Code uses all 16 bits of the data byte, including the
sign bit.
Negative Temperature = (ADC Code(dec) − 32,768)/128
where the MSB is removed from the ADC code.
Temperature data in the temperature value register, the TCRIT
setpoint register, the THIGH setpoint register, and the TLOW
setpoint register are represented by a 13-bit, twos complement
word. The MSB is the temperature sign bit. The three LSBs,
Bit 0 to Bit 2, on power-up, are not part of the temperature
13-Bit Temperature Data Format
Positive Temperature = ADC Code(dec)/16
Negative Temperature = (ADC Code(dec) − 8192)/16
where ADC Code uses all 13 bits of the data byte, including the
sign bit.
conversion result and are flag bits for TCRIT, THIGH, and TLOW
Table 5 shows the 13-bit temperature data format without
Bit 0 to Bit 2.
.
Negative Temperature = (ADC Code(dec) − 4096)/16
where the MSB is removed from the ADC code.
The number of bits in the temperature data-word can be extended
to 16 bits, twos complement by setting Bit 7 to 1 in the configuration
register (Register Address 0x01). When using a 16-bit temperature
data value, Bit 0 to Bit 2 are not used as flag bits and are instead
the LSB bits of the temperature value. The power-on default
setting has a 13-bit temperature data value.
10-Bit Temperature Data Format
Positive Temperature = ADC Code(dec)/2
Negative Temperature = (ADC Code(dec) − 1024)/2
where ADC Code uses all 10 bits of the data byte, including the
sign bit.
Reading back the temperature from the temperature value register
requires a 2-byte read. Designers that use a 9-bit temperature
data format can still use the ADT7320 by ignoring the last four
LSBs of the 13-bit temperature value. These four LSBs are Bit 3
to Bit 6 in Table 5.
Negative Temperature = (ADC Code(dec) − 512)/2
where the MSB is removed from the ADC Code.
9-Bit Temperature Data Format
Positive Temperature = ADC Code(dec)
Negative Temperature = ADC Code(dec) − 512
Table 5. 13-Bit Temperature Data Format
Digital Output
(Binary) Bits[1ꢀ:3]
Digital
Output (Hex)
Temperature
−4±°C
where ADC Code uses all nine bits of the data byte, including
the sign bit.
1 11±1 1±±± ±±±±
1 111± ±111 ±±±±
1 1111 1111 1111
± ±±±± ±±±± ±±±±
± ±±±± ±±±± ±±±1
± ±±±1 1±±1 ±±±±
± ±11± 1±±1 ±±±±
± ±111 11±1 ±±±±
± 1±±1 ±11± ±±±±
±x1D8±
±x1E7±
±x1FFF
±x±±±
±x±±1
±x19±
±x69±
±x7D±
±x96±
−25°C
−±.±625°C
±°C
Negative Temperature = ADC Code(dec) − 256
where the MSB is removed from the ADC Code.
+±.±625°C
+25°C
+1±5°C
+125°C
+15±°C
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REGISTERSC
The ADT7320 contains eight registers:
STATUS REGISTER
This 8-bit read-only register (Register Address 0x00) reflects the
status of the overtemperature and undertemperature interrupts
that can cause the CT and INT pins to go active. It also reflects
the status of a temperature conversion operation. The interrupt
flags in this register are reset by a read operation to the status
register and/or when the temperature value returns within the
•
•
•
•
A status register
A configuration register
Five temperature registers
An ID register
The status register, temperature value register, and the ID
register are read-only.
RDY
temperature limits including hysteresis. The
read from the temperature value register. In one-shot and 1 SPS
RDY
bit is reset after a
modes, the
bit is reset after a write to the one-shot bits.
Table 6. ADT7320 Registers
Register Address
Description
Power-On Default
±x8±
±x±±
±x±±±±
±xCX
±x498± (147°C)
±x±5 (5°C)
±x2±±± (64°C)
±x±5±± (1±°C)
±x±±
±x±1
±x±2
±x±3
±x±4
±x±5
±x±6
±x±7
Status
Configuration
Temperature value
ID
TCRIT setpoint
THYST setpoint
THIGH setpoint
TLOW setpoint
Table 7. Status Register (Register Address 0x00)
Bit(s)
[±:3]
[4]
Default Value
Type Name
Description
±±±±
±
R
R
Unused Reads back ±.
TLOW
THIGH
TCRIT
RDY
This bit is set to 1 when the temperature goes below the TLOW temperature limit. This bit
clears to ± when the status register is read and/or when the temperature measured goes
back above the limit set in the TLOW + THYST setpoint registers.
[5]
[6]
[7]
±
±
1
R
R
R
This bit is set to 1 when the temperature goes above the THIGH temperature limit. This bit
clears to ± when the status register is read and/or when the temperature measured goes
back below the limit set in the THIGH − THYST setpoint registers.
This bit is set to 1 when the temperature goes above the TCRIT temperature limit. This bit
clears to ± when the status register is read and/or when the temperature measured goes
back below the limit set in the TCRIT − THYST setpoint registers.
This bit goes low when the temperature conversion result is written into the temperature
value register. It is reset to 1 when the temperature value register is read. In one-shot and
1 SPS modes, this bit is reset after a write to the one-shot bits.
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DT73.±
CONFIGURATION REGISTER
This 8-bit read/write register stores various configuration modes
for the ADT7320, including shutdown, overtemperature and
undertemperature interrupts, one-shot, continuous conversion,
interrupt pins polarity, and overtemperature fault queues.
Table 8. Configuration Register (Register Address 0x01)
Default
Value
Bit
Type Name
Description
[±:1]
±±
R/W
Fault queue
These two bits set the number of undertemperature/overtemperature faults that can
occur before setting the INT and CT pins. This helps to avoid false triggering due to
temperature noise.
±± = 1 fault (default).
±1 = 2 faults.
1± = 3 faults.
11 = 4 faults.
[2]
±
R/W
R/W
R/W
R/W
CT pin polarity
INT pin polarity
INT/CT mode
This bit selects the output polarity of the CT pin.
± = active low.
1 = active high.
[3]
±
This bit selects the output polarity of the INT pin.
± = active low.
1 = active high.
[4]
±
This bit selects between comparator mode and interrupt mode.
± = interrupt mode.
1 = comparator mode.
[5:6]
±±
Operation mode These two bits set the operational mode for the ADT732±.
±± = continuous conversion (default). When one conversion is finished, the ADT732±
starts another.
±1 = one shot. Conversion time is typically 24± ms.
1± = 1 SPS mode. Conversion time is typically 6± ms. This operational mode reduces the
average current consumption.
11 = shutdown. All circuitry except interface circuitry is powered down.
This bit sets up the resolution of the ADC when converting.
[7]
±
R/W
Resolution
± = 13-bit resolution. Sign bit + 12 bits gives a temperature resolution of ±.±625°C.
1 = 16-bit resolution. Sign bit + 15 bits gives a temperature resolution of ±.±±78125°C.
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ID REGISTER
TEMPERATURE VALUE REGISTER
This 8-bit read-only register (Register Address 0x03) stores
the manufacturer ID in Bit 7 to Bit 3 and the silicon revision in
Bit 2 to Bit 0.
The temperature value register stores the temperature measured
by the internal temperature sensor. The temperature is stored as
a 16-bit twos complement format. The temperature is read back
from the temperature value register (Register Address 0x02) as a
16-bit value.
TCRIT SETPOINT REGISTER
The 16-bit TCRIT setpoint register (Register Address 0x04) stores
the critical overtemperature limit value. A critical overtemperature
event occurs when the temperature value stored in the temperature
value register exceeds the value stored in this register. The CT
pin is activated if a critical overtemperature event occurs. The
temperature is stored in twos complement format with the MSB
being the temperature sign bit.
Bit 2, Bit 1, and Bit 0 are event alarm flags for TCRIT, THIGH, and
TLOW. When the ADC is configured to convert the temperature
to a 16-bit digital value, Bit 2, Bit 1, and Bit 0 are no longer used
as flag bits and are, instead, used as the LSB bits for the extended
digital value.
The default setting for the TCRIT setpoint is 147°C.
Table 9. Temperature Value Register (Register Address 0x02)
Bit
Default Value
Type
Name
Description
[±]
±
R
TLOW flag/LSB± Flags a TLOW event if the configuration register, Register Address ±x±1[7] = ±
(13-bit resolution). When the temperature value is below TLOW,, this bit it set to 1.
Contains the Least Significant Bit ± of the 15-bit temperature value if the
configuration register, Register Address ±x±1[7] = 1 (16-bit resolution).
[1]
[2]
±
±
R
R
THIGH flag/LSB1 Flags a THIGH event if the configuration register, Register Address ±x±1[7] = ±
(13-bit resolution). When the temperature value is above THIGH, this bit it set to 1.
Contains the Least Significant Bit 1 of the 15-bit temperature value if the
configuration register, Register Address ±x±1[7] = 1 (16-bit resolution).
TCRIT flag/LSB2 Flags a TCRIT event if the configuration register, Register Address ±x±1[7] = ±
(13-bit resolution). When the temperature value exceeds TCRIT, this bit it set to 1.
Contains the Least Significant Bit 2 of the 15-bit temperature value if the
configuration register, Register Address ±x±1[7] = 1 (16-bit resolution).
[3:7]
[8:14]
[15]
±±±±±
±±±±±±±
±
R
R
R
Temp
Temp
Sign
Temperature value in twos complement format.
Temperature value in twos complement format.
Sign bit, indicates if the temperature value is negative or positive.
Table 10. ID Register (Register Address 0x03)
Bit
Default Value
Type
Name
Description
[2:±]
[7:3]
XXX
R
R
Revision ID
Contains the silicon revision identification number.
11±±±
Manufacture ID Contains the manufacturer identification number.
Table 11. TCRIT Setpoint Register (Register Address 0x04)
Bit
Default Value
Type
Name
Description
[15:±]
±x498±
R/W
TCRIT
16-bit critical overtemperature limit, stored in twos complement format.
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DT73.±
TLOW SETPOINT REGISTER
THYST SETPOINT REGISTER
The 16-bit TLOW setpoint register (Register Address 0x07) stores
the undertemperature limit value. An undertemperature event
occurs when the temperature value stored in the temperature
value register is less than the value stored in this register. The
INT pin is activated if an undertemperature event occurs. The
temperature is stored in twos complement format with the MSB
being the temperature sign bit.
The THYST setpoint 8-bit register (Register Address 0x05) stores
the temperature hysteresis value for the THIGH, TLOW, and TCRIT
temperature limits. The temperature hysteresis value is stored in
straight binary format using four LSBs. Increments are possible
in steps of 1°C from 0°C to 15°C. The value in this register is
subtracted from the THIGH and TCRIT values and added to the
TLOW value to implement hysteresis.
The default setting for the TLOW setpoint is 10°C.
The default setting for the THYST setpoint is 5°C.
THIGH SETPOINT REGISTER
The 16-bit THIGH setpoint register (Register Address 0x06) stores
the overtemperature limit value. An overtemperature event occurs
when the temperature value stored in the temperature value
register exceeds the value stored in this register. The INT pin is
activated if an overtemperature event occurs. The temperature
is stored in twos complement format with the most significant
bit being the temperature sign bit.
The default setting for the THIGH setpoint is 64°C.
Table 12. THYST Setpoint Register (Register Address 0x05)
Bit
Default Value Type Name Description
[±:3]
[4:7]
±1±1
±±±±
R/W
R/W
THYST
N/A
Hysteresis value, from ±°C to 15°C. Stored in straight binary format. The default setting is 5°C.
Not used.
Table 13. THIGH Setpoint Register (Register Address 0x06)
Bit
Default Value
Type Name Description
[±:15]
±x2±±±
R/W
THIGH 16-bit overtemperature limit, stored in twos complement format.
Table 14. TLOW Setpoint Register (Register Address 0x07)
Bit
Default Value
Type Name Description
[±:15]
±x±5±±
R/W
TLOW
16-bit undertemperature limit, stored in twos complement format.
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SERI LCINTERF °EC
PULL-UP
V
V
DD
DD
V
10kΩ 10kΩ
DD
0.1µF
ADT7320
GND
CT
SCLK
DOUT
DIN
MICROCONTROLLER
INT
CS
Figure 15. Typical SPI Interface Connection
The ADT7320 has a 4-wire serial peripheral interface (SPI). The
interface has a data input pin (DIN) for inputting data to the device,
a data output pin (DOUT) for reading data back from the device,
and a data clock pin (SCLK) for clocking data into and out of
Bit C7 of the command byte must be set to 0 to successfully begin a
bus transaction. The SPI interface does not work correctly if a 1
is written into this bit.
Bit C6 is the read/write bit; 1 indicates a read, and 0 indicates a write.
CS
the device. A chip select pin ( ) enables or disables the serial
CS
interface.
is required for correct operation of the interface.
Bits[C5:C3] contain the target register address. One register can
be read from or written to per bus transaction.
Data is clocked out of the ADT7320 on the negative edge of SCLK,
and data is clocked into the device on the positive edge of SCLK.
Bit C2 activates a continuous read mode on the temperature value
register only. When this bit is set, the serial interface is configured
so that the temperature value register can be continuously read.
When the command word is 01010100 (0x54), the contents of
the temperature value register can be read out without requiring
repeated writes to set the address bits. Simply sending 16 SCLK
clocks to the ADT7320 clocks the contents of the temperature
value register onto the DOUT pin.
SPI COMMAND BYTE
All data transactions on the bus begin with the master taking
CS
from high to low and sending out the command byte. This
indicates to the ADT7320 whether the transaction is a read or a
write and provides the address of the register for the data transfer.
Table 15 shows the command byte.
Table 15. Command Byte
C7 C6
Cꢀ
C4
C3
C2
C1 C0
±
R/W
Register address
Continuous read
±
±
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DT73.±
Figure 16 shows a write to an 8-bit register, and Figure 17 shows
a write to a 16-bit register.
WRITING DATA
Data is written to the ADT7320 in eight bits or 16 bits, depending
on the addressed register. The first byte written to the device is
the command byte, with the read/write bit set to 0. The master
then supplies the 8-bit or 16-bit input data on the DIN line. The
ADT7320 clocks the data into the register addressed in the
command byte on the positive edge of SCLK. The master
The master must begin a new write transaction on the bus for
every register write. Only one register is written to per bus
transaction.
CS
finishes the write by pulling
high.
CS
SCLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
8-BIT DATA
8-BIT COMMAND BYTE
CONT
READ
0
0
0
R/W REGISTER ADDR
C4
C0
D7
D6
D5
D4
D3
D2
D1
D0
C3
C1
C7
C6
C5
C2
DIN
Figure 16. Writing to an 8-Bit Register
CS
SCLK
22
23
24
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
16-BIT DATA
8-BIT COMMAND BYTE
CONT
READ
0
0
C1
R/W
C6
REGISTER ADDR
C5 C4 C3
0
C0
C7
C2
D15 D14 D13
D12 D11 D10
D9
D8
D7
D2
D1
D0
DIN
Figure 17. Writing to a 16-Bit Register
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CS
SCLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
8-BIT COMMAND WORD
CONT
0
0
R/W REGISTER ADDR
0
READ
DIN
C4
C0
C3
C1
C7
C6
C5
C2
8-BIT DATA
D5 D4 D3
D7
D6
D2
D1
D0
DOUT
Figure 18. Read from an 8-Bit Register
CS
SCLK
22
23
24
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
8-BIT COMMAND BYTE
CONT
READ
0
0
C1
R/W
C6
REGISTER ADDR
C4
0
DIN
C0
C3
C5
C2
C7
16-BIT DATA
D10
D9
D8
D1
D0
DOUT
D7
D2
D15
D14
D12
D13
D11
Figure 19. Read from a 16-Bit Register
READING DATA
INTERFACING TO DSPs OR MICROCONTROLLERS
A read transaction begins when the master writes the command
byte to the ADT7320 with the read/write bit set to 1. The master
then supplies 8 or 16 clock pulses, depending on the addressed
register, and the ADT7320 clocks out data from the addressed
register on the DOUT line. Data is clocked out on the first
falling edge of SCLK following the command byte.
CS
used as a frame syn-
The ADT7320 can be operated with
chronization signal. This scheme is useful for DSP interfaces.
CS
In this case, the first bit (MSB) is effectively clocked out by
CS
because
normally occurs after the falling edge of SCLK in
DSPs. SCLK can continue to run between data transfers,
provided that the timing numbers are obeyed.
CS
The read transaction finishes when the master takes high.
CS
can be tied to ground and the serial interface can operate in
a 3-wire mode. DIN, DOUT, and SCLK are used to communicate
with the ADT7320 in this mode.
The master must begin a new read transaction on the bus for
every register read. Only one register is read per bus transaction.
However, in continuous read mode, Command Byte C2 = 1 and
the temperature value register can be read from continuously.
The master sends 16 clock pulses on SCLK, and the temperature
value is clocked out on DOUT. See Figure 18 and Figure 19.
For microcontroller interfaces, it is recommended that SCLK
idle high between data transfers.
SERIAL INTERFACE RESET
The serial interface can be reset by writing a series of 1s on the DIN
input. If a Logic 1 is written to the ADT7320 line for at least 32 serial
clock cycles, the serial interface is reset. This ensures that the interface
can be reset to a known state if the interface gets lost due to a software
error or some glitch in the system. Reset returns the interface to
the state in which it is expecting a write to the communications
register. This operation resets the contents of all registers to their
power-on values. Following a reset, the user should allow a period
of 500 μs before addressing the serial interface.
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DT73.±
INTC NDC°TCOUTPUTSC
Comparator Mode
The INT and CT pins are open drain outputs, and both pins
require a 10 kΩ pull-up resistor to VDD
.
In comparator mode, the INT pin returns to its inactive status
when the temperature drops below the THIGH − THYST limit or
rises above the TLOW + THYST limit.
UNDERTEMPERATURE AND OVERTEMPERATURE
DETECTION
Putting the ADT7320 into shutdown mode does not reset the
INT state in comparator mode.
The INT and CT pins have two undertemperature/overtemperature
modes: comparator mode and interrupt mode. The interrupt
mode is the default power-up overtemperature mode. The INT
output pin becomes active when the temperature is greater than
the temperature stored in the THIGH setpoint register or less than
the temperature stored in the TLOW setpoint register. How this
pin reacts after this event depends on the overtemperature
mode selected.
Interrupt Mode
In interrupt mode, the INT pin goes inactive when any ADT7320
register is read. When the INT pin is reset, it goes active again
only when the temperature is greater than the temperature stored
in the THIGH setpoint register or less than the temperature stored
in the TLOW setpoint register.
Figure 20 illustrates the comparator and interrupt modes for
events exceeding the THIGH limit with both pin polarity settings.
Figure 21 illustrates the comparator and interrupt modes for
events exceeding the TLOW limit with both pin polarity settings.
Placing the ADT7320 into shutdown mode resets the INT pin
in interrupt mode.
TEMPERATURE
82°C
81°C
80°C
79°C
78°C
77°C
76°C
75°C
74°C
73°C
T
HIGH
T
– T
HYST
HIGH
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE LOW
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE LOW
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE HIGH
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE HIGH
TIME
READ
READ
READ
Figure 20. INT Output Temperature Response Diagram for THIGH Overtemperature Events
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TEMPERATURE
–13°C
–14°C
–15°C
–16°C
–17°C
–18°C
–19°C
–20°C
–21°C
–22°C
T
LOW
+ T
HYST
T
LOW
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE LOW
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE LOW
INT PIN
(COMPARATOR MODE)
POLARITY = ACTIVE HIGH
INT PIN
(INTERRUPT MODE)
POLARITY = ACTIVE HIGH
TIME
READ
READ
READ
Figure 21. INT Output Temperature Response Diagram for TLOW Undertemperature Events
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DT73.±
PPLI° TIONSCINFORM TIONC
THERMAL RESPONSE TIME
TEMPERATURE MONITORING
The time required for a temperature sensor to settle to a specified
accuracy is a function of the thermal mass of the sensor and the
thermal conductivity between the sensor and the object being sensed.
Thermal mass is often considered equivalent to capacitance.
Thermal conductivity is commonly specified using the symbol,
Q, and can be thought of as thermal resistance. It is commonly
specified in units of degrees per watt of power transferred across
the thermal joint. The time required for the part to settle to the
desired accuracy is dependent on the thermal contact established
in that particular application and the equivalent power of the
heat source. In most applications, the settling time is best
determined empirically.
The ADT7320 is ideal for monitoring the thermal environment
within hazardous automotive applications. The die accurately reflects
the exact thermal conditions that affect nearby integrated circuits.
The ADT7320 measures and converts the temperature at the
surface of its own semiconductor chip. When the ADT7320 is
used to measure the temperature of a nearby heat source, the
thermal impedance between the heat source and the ADT7320
must be considered.
When the thermal impedance is determined, the temperature of
the heat source can be inferred from the ADT7320 output. As
much as 60% of the heat transferred from the heat source to the
thermal sensor on the ADT7320 die is discharged via the copper
tracks and the bond pads. Of the pads on the ADT7320, the
GND pad transfers most of the heat. Therefore, to measure the
temperature of a heat source, it is recommended that the thermal
resistance between the ADT7320 GND pad and the GND of the
heat source be reduced as much as possible.
SUPPLY DECOUPLING
The ADT7320 should be decoupled with a 0.1 μF ceramic capacitor
between VDD and GND. This is particularly important when the
ADT7320 is mounted remotely from the power supply. Precision
analog products, such as the ADT7320, require a well-filtered
power source.
Because the ADT7320 operates from a single supply, it may
seem convenient to tap into the digital logic power supply.
Unfortunately, the logic supply is often a switch-mode design,
which generates noise in the 20 kHz to 1 MHz range. In addition,
fast logic gates can generate glitches hundreds of millivolts in
amplitude due to wiring resistance and inductance.
If possible, the ADT7320 should be powered directly from the
system power supply. This arrangement, shown in Figure 22,
isolates the analog section from the logic-switching transients.
Even if a separate power supply trace is not available, generous
supply bypassing reduces supply-line induced errors. Local supply
bypassing consisting of a 0.1 μF ceramic capacitor is critical for
the temperature accuracy specifications to be achieved. This
decoupling capacitor must be placed as close as possible to the
VDD pin of the ADT7320.
TTL/CMOS
LOGIC
CIRCUITS
0.1µF
ADT7320
POWER
SUPPLY
Figure 22. Use of Separate Traces to Reduce Power Supply Noise
Rev. PrA | Page 23 of 24
DT73.±C
PutlBmBnruyCTtAhnBArlCDrar
OUTLINECDIMENSIONSC
4.10
4.00 SQ
3.90
0.35
0.30
0.25
PIN 1
INDICATOR
PIN 1
INDICATOR
13
16
1
0.65
BSC
12
EXPOSED
PAD
2.70
2.60 SQ
2.50
4
5
9
8
0.45
0.40
0.35
0.25 MIN
TOP VIEW
BOTTOM VIEW
0.80
0.75
0.70
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
0.05 MAX
0.02 NOM
COPLANARITY
0.08
SECTION OF THIS DATA SHEET.
SEATING
PLANE
0.20 REF
COMPLIANT TO JEDEC STANDARDS MO-220-WGGC.
Figure 23. 16-Lead Lead Frame Chip Scale Package [LFCSP_WQ]
4 mm × 4 mm Body, Very Very Thin Quad
(CP-16-17)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature Range
Temperature Accuracy2
±±.25°C
±±.25°C
±±.25°C
Package Description
Package Option
CP-16-17
CP-16-17
ADT732±UCPZ
ADT732±UCPZ-R2
ADT732±UCPZ-RL7
EVAL-ADT7X2±EBZ
−4±°C to +15±°C
−4±°C to +15±°C
−4±°C to +15±°C
16-lead LFCSP_WQ
16-Lead LFCSP_WQ
16-Lead LFCSP_WQ
Evaluation Board
CP-16-17
1 Z = RoHS Compliant Part.
2 Maximum accuracy over the −2±°C to +1±5°C temperature range.
©2010 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
PR09012-0-6/10(PrA)
Rev. PrA | Page 24 of 24
相关型号：
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DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 2Cel, RECTANGULAR, SURFACE MOUNT, LEAD FREE, LFCSP-8
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DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 2Cel, RECTANGULAR, SURFACE MOUNT, LEAD FREE, LFCSP-8
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