ADT7311WTRZ-RL [ADI]
Automotive, ±0.5°C Accurate, 16-Bit Digital SPI Temperature Sensor;
| 型号： | ADT7311WTRZ-RL |
| 厂家： | 
ADI |
| 描述： | Automotive, ±0.5°C Accurate, 16-Bit Digital SPI Temperature Sensor 输出元件 传感器 换能器 |
| 文件： | 总25页 (文件大小：419K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Automotive, ± ±0.5° Aꢀꢀuꢁrte, ꢂ16-it
Digitrl SPI Tempeꢁrtuꢁe Sensoꢁ
Drtr Sheet
ADT73ꢂꢂ
FEATURES
GENERAL DESCRIPTION
Qualified for automotive applications
High performance
Temperature accuracy
0.ꢀ5C from −405C to +10ꢀ5C (2.7 V to 3.6 V)
0.45C from −405C to +10ꢀ5C (3.0 V)
16-bit temperature resolution: 0.00785C
Fast first conversion on power-up of 6 ms
Easy implementation
The ADT7311 is a high accuracy digital temperature sensor
in a narrow 8-lead SOIC package. It contains a band gap
temperature reference and a 16-bit ADC to monitor and digitize
the temperature to a 0.0078°C resolution. The ADC resolution,
by default, is set to 13 bits (0.0625°C). The ADC resolution is a
user programmable mode that can be changed through the
serial interface.
No temperature calibration/correction required by user
No linearity correction required
Low power
Power saving 1 sample per second (SPS) mode
700 μW typical at 3.3 V in normal mode
7 μW typical at 3.3 V in shutdown mode
Wide operating ranges
The ADT7311 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 ADT7311 has a shutdown mode that
powers down the device and offers a shutdown current of
typically 2 μA. The ADT7311 is rated for operation over the
−40°C to +150°C temperature range.
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.
Temperature range: −405C to +1ꢀ05C
Voltage range: 2.7 V to ꢀ.ꢀ V
Programmable interrupts
Critical overtemperature interrupt
Overtemperature/undertemperature interrupt
SPI-compatible interface
8-lead narrow SOIC RoHS-compliant package
PRODUCT HIGHLIGHTS
APPLICATIONS
1. Ease of use, no calibration or correction required by the user.
2. Low power consumption.
Battery management
Climate control and infotainment
Lighting
Powertrain
3. Excellent long-term stability and reliability.
4. Packaged in an 8-lead SOIC, RoHS-compliant package.
Thermocouple cold junction compensation
GPS
FUNCTIONAL BLOCK DIAGRAM
1
2
3
4
SCLK
DOUT
ADT7311
INTERNAL
OSCILLATOR
INTERNAL
REFERENCE
DIN
CS
6
5
CT
T
T
T
CRIT
HIGH
LOW
Σ-∆
MODULATOR
TEMPERATURE
SENSOR
TEMPERATURE
VALUE
CONFIGURATION,
STATUS, AND
INT
REGISTER
ID REGISTERS
T
T
HYST
REGISTER
CRIT
REGISTER
FILTER
LOGIC
7
8
GND
T
T
HIGH
REGISTER
LOW
REGISTER
V
DD
Figure 1.
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2011 Analog Devices, Inc. All rights reserved.
ADT7311* PRODUCT PAGE QUICK LINKS
Last Content Update: 02/23/2017
COMPARABLE PARTS
View a parametric search of comparable parts.
DISCUSSIONS
View all ADT7311 EngineerZone Discussions.
DOCUMENTATION
Data Sheet
SAMPLE AND BUY
Visit the product page to see pricing options.
• ADT7311: Automotive, ±0.5°C Accurate, 16-BitDigital SPI
Temperature Sensor
TECHNICAL SUPPORT
Submit a technical question or find your regional support
number.
REFERENCE DESIGNS
• CN0281
DOCUMENT FEEDBACK
DESIGN RESOURCES
• ADT7311 Material Declaration
• PCN-PDN Information
Submit feedback for this data sheet.
• Quality And Reliability
• Symbols and Footprints
This page is dynamically generated by Analog Devices, Inc., and inserted into this data sheet. A dynamic change to the content on this page will not
trigger a change to either the revision number or the content of the product data sheet. This dynamic page may be frequently modified.
ADT73ꢂꢂ
Drtr Sheet
TA-LE OF °ONTENTS
Features .............................................................................................. 1
Configuration Register .............................................................. 14
Temperature Value Register...................................................... 15
ID Register................................................................................... 15
TCRIT Setpoint Register ............................................................... 15
THYST Setpoint Register............................................................... 16
THIGH Setpoint Register .............................................................. 16
TLOW Setpoint Register ............................................................... 16
Serial Peripheral Interface............................................................. 17
SPI Command Byte.................................................................... 17
Writing Data ............................................................................... 18
Reading Data............................................................................... 19
Interfacing to DSPs or Microcontrollers................................. 19
Serial Interface Reset.................................................................. 19
INT and CT Outputs...................................................................... 20
Undertemperature and Overtemperature Detection ............ 20
Applications Information.............................................................. 22
Thermal Response Time ........................................................... 22
Supply Decoupling ..................................................................... 22
Powering from a Switching Regulator..................................... 22
Temperature Monitoring........................................................... 22
Quick Guide to Measuring Temperature ................................ 22
Outline Dimensions....................................................................... 23
Ordering Guide .......................................................................... 23
Automotive Products................................................................. 23
Applications....................................................................................... 1
General Description......................................................................... 1
Product Highlights ........................................................................... 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
Shutdown..................................................................................... 11
Fault Queue ................................................................................. 11
Temperature Data Format......................................................... 12
Temperature Conversion Formulas ......................................... 12
Registers........................................................................................... 13
Status Register............................................................................. 13
REVISION HISTORY
9/11—Revision 0: Initial Version
Rev. 0 | Page 2 of 24
Drtr Sheet
ADT73ꢂꢂ
SPE°IFI°ATIONS
TA = −40°C to +150°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
−0.05
0.4
0.44
°C
°C
°C
°C
°C
°C
°C
Bits
TA = −40°C to +105°C, VDD = 3.0 V
TA = −40°C to +105°C, VDD = 2.7 V to 3.3 V
TA = −40°C to +125°C, VDD = 3.0 V
TA = −40°C to +105°C, VDD = 2.7 V to 3.6 V
TA = −40°C to +150°C, VDD = 2.7 V to 3.6 V
TA = −40°C to +105°C, VDD = 4.5 V to 5.5 V
TA = −40°C to +150°C, VDD = 2.7 V to 5.5 V
Twos complement temperature value of sign bit plus
12 ADC bits (power-up default resolution)
0.5
0.5
0.7
0.ꢀ
1.0
ADC Resolution
13
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
Temperature Conversion Time
Fast Temperature ConversionTime
1 SPS Conversion Time
Temperature Hysteresis
Repeatability
0.0625
0.007ꢀ
240
6
60
0.002
0.015
0.1
°C
°C
ms
ms
ms
°C
13-bit resolution (sign + 12 bits)
16-bit resolution (sign + 15 bits)
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
DC PSRR
°C/V
TA = 25°C
DIGITAL OUTPUTS (CT, INT), OPEN
DRAIN
High Output Leakage Current, IOH
Output Low Voltage, VOL
Output High Voltage, VOH
0.1
2
5
0.4
μA
V
V
CT and INT pins pulled up to 5.5 V
IOL = 2 mA at 5.5 V, IOL = 1 mA at 3.3 V
0.7 ×
VDD
Output Capacitance, COUT
DIGITAL INPUTS (DIN, SCLK, CS)
Input Current
Input Low Voltage, VIL
Input High Voltage, VIH
pF
1
μA
V
V
VIN = 0 V to VDD
0.4
0.7 ×
VDD
Pin Capacitance
5
10
pF
V
DIGITAL OUTPUT (DOUT)
Output High Voltage, VOH
VOH
0.3
−
ISOURCE = ISINK = 200 μA
IOL = 200 μA
Output Low Voltage, VOL
Output Capacitance, COUT
POWER REQUIREMENTS
Supply Voltage
Supply Current
At 3.3 V
0.4
50
V
pF
2.7
5.5
V
210
250
265
300
μA
μA
Peak current while converting, SPI interface inactive
Peak current while converting, SPI interface inactive
At 5.5 V
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
Rev. 0 | Page 3 of 24
ADT7311
Data Sheet
Parameter
Min
Typ
Max
Unit
Test Conditions/Comments
Shutdown Current
At 3.3 V
At 5.5 V
Power Dissipation Normal Mode
Power Dissipation 1 SPS
2.0
5.2
700
150
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 lifetime drift.
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
Unit
Conditions/Comments
t1
t2
t3
t4
t5
t6
0
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
CS falling edge to SCLK active edge setup time
SCLK high pulse width
SCLK low pulse width
Data setup time prior to SCLK rising edge
Data hold time after SCLK rising edge
Data access time after SCLK falling edge
VDD = 4.5 V to 5.5 V
100
100
30
25
5
60
80
10
80
0
VDD = 2.7 V to 3.6 V
Bus relinquish time after CS inactive edge
3
t7
t8
t9
SCLK inactive edge to CS rising 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 low
0
60
80
10
t10
1 Sample tested during initial release to ensure compliance. All input signals are specified with tR = tF = 5 ns (10% to 90% of VDD) and timed from a voltage level of 1.6 V.
2 See Figure 2.
3 This means that the times quoted in the timing characteristics in Table 2 are the true bus relinquish times of the part and, as such, are independent of external bus
loading capacitances.
CS
t1
t2
1
t8
t3
6
7
8
9
10
23
24
2
3
SCLK
t4
t5
MSB
LSB
DIN
t6
t10
t9
DOUT
LSB
MSB
t7
Figure 2. Detailed SPI Timing Diagram
Rev. 0 | Page 4 of 24
Drtr Sheet
ADT73ꢂꢂ
A-SOLUTE MAXIMUM RATINGS
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
−0.3 V to +7 V
−0.3 V to VDD + 0.3 V
−0.3 V to VDD + 0.3 V
−0.3 V to VDD + 0.3 V
−0.3 V to VDD + 0.3 V
−0.3 V to VDD + 0.3 V
2.0 kV
−40°C to +150°C
−65°C to +160°C
150°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 Range1
Storage Temperature Range
Maximum Junction Temperature, TJMAX
ꢀ-Lead SOIC_N (R-ꢀ)
ESD CAUTION
Power Dissipation2
Thermal Impedance4
WMAX = (TJMAX − TA )/θJA
3
θJA, Junction-to-Ambient (Still Air)
θJC, Junction-to-Case
121°C/W
56°C/W
IR Reflow Soldering
220°C
Peak Temperature (RoHS-Compliant
Package)
260°C (0°C)
Time at Peak Temperature
Ramp-Up Rate
Ramp-Down Rate
20 sec to 40 sec
3°C/sec maximum
−6°C/sec maximum
ꢀ minutes maximum
Time from 25°C to Peak Temperature
1 Operating at extended temperatures over prolonged periods depends on
the lifetime performance of the part. Consult your local Analog Devices, Inc.,
account representative for more details.
2 Value relates to package being used on a standard 2-layer PCB. This gives a
worst-case θJA and θJC.
3 TA = ambient temperature.
4 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.
Rev. 0 | Page 5 of 24
ADT73ꢂꢂ
Drtr Sheet
PIN °ONFIGURATION AND FUN°TION DES°RIPTIONS
SCLK
DOUT
DIN
1
2
3
4
8
7
6
5
V
DD
ADT7311
GND
CT
TOP VIEW
(Not to Scale)
CS
INT
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
2
3
SCLK
DOUT
DIN
Serial Clock Input. The serial clock is used to clock in and clock out data to and from any register of the ADT7311.
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 part’s control registers is provided on this input. Data is clocked
into the registers on the rising edge of SCLK.
4
5
CS
Chip Select Input. The device is selected when this input is low. The device is disabled when this pin is high.
INT
Overtemperature and Undertemperature Indicator. Logic output. The power-up default setting is as an active
low comparator interrupt. Open-drain configuration. A pull-up resistor is required, typically 10 kΩ.
6
CT
Critical Overtemperature Indicator. Logic output. Power-up default polarity is active low. Open-drain
configuration. A pull-up resistor is required, typically 10 kΩ.
7
ꢀ
GND
VDD
Analog and Digital Ground.
Positive Supply Voltage (2.7 V to 5.5 V). The supply should be decoupled with a 0.1 μF ceramic capacitor to GND.
Rev. 0 | Page 6 of 24
Drtr Sheet
ADT73ꢂꢂ
TYPI°AL PERFORMAN°E °HARA°TERISTI°S
1.0
300
250
200
150
100
50
5.5V CONTINUOUS
CONVERSION
0.8
0.6
0.4
MAX ACCURACY LIMITS
3.0V CONTINUOUS
CONVERSION
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
5.5V 1SPS
3.0V 1SPS
MAX ACCURACY LIMITS
0
–100
–60 –40 –20
0
20
40
60
80 100 120 140 160
–50
0
50
100
150
200
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 4. Temperature Accuracy at 3 V
Figure 6. Operating Supply Current vs. Temperature
8
7
6
5
4
3
2
1
0
1.0
0.8
MAX ACCURACY LIMITS
0.6
0.4
5.5V
0.2
5.0V
4.5V
0
–0.2
–0.4
–0.6
–0.8
–1.0
3.6V
3.0V
2.7V
MAX ACCURACY LIMITS
–100
–50
0
50
100
150
200
–60 –40 –20
0
20
40
60
80 100 120 140 160
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 5. Temperature Accuracy at 5 V
Figure 7. Shutdown Current vs. Temperature
Rev. 0 | Page 7 of 24
ADT73ꢂꢂ
Drtr Sheet
300
250
200
150
100
50
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
Rev. 0 | Page ꢀ of 24
Drtr Sheet
ADT73ꢂꢂ
THEORY OF OPERATION
CIRCUIT INFORMATION
Σ-∆ MODULATOR
INTEGRATOR
The ADT7311 is a high accuracy digital temperature sensor that
uses a 16-bit ADC to monitor and digitize the temperature to
0.0078°C of resolution. The ADC resolution, by default, is set to
13 bits (0.0625°C). An internal temperature sensor generates a
voltage proportional to absolute temperature, which is com-
pared to an internal voltage reference and input into a precision
digital modulator.
COMPARATOR
VOLTAGE REF
AND VPTAT
1-BIT
DAC
1-BIT
The internal temperature sensor has high accuracy and linearity
over the entire rated temperature range without needing correc-
tion or calibration by the user.
TEMPERATURE
VALUE
REGISTER
CLOCK
GENERATOR
LPF DIGITAL
FILTER
13-BIT/
16-BIT
Figure 11. Σ-∆ Modulator
The sensor output is digitized by a sigma-delta (Σ-Δ) modulator,
also known as the charge balance type analog-to-digital conver-
ter. This type of converter utilizes time-domain oversampling
and a high accuracy comparator to deliver 16 bits of resolution
in an extremely compact circuit.
TEMPERATURE MEASUREMENT
In normal mode (default power-up mode), the ADT7311 runs
an automatic conversion sequence. During this automatic
conversion sequence, a conversion typically takes 240 ms to
complete and the ADT7311 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.
CONVERTER DETAILS
The Σ-Δ 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 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.
On 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.
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 modulated output of the comparator is encoded using a
circuit technique that results in SPI temperature data.
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.
Rev. 0 | Page 9 of 24
ADT73ꢂꢂ
Drtr Sheet
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
1 SPS MODE
ONE-SHOT 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 6 and 0 to Bit 5 of the configuration register
(Register Address 0x01).
Setting Bit 6 to 0 and Bit 5 to 1 of the configuration register
(Register Address 0x01) enables the one-shot mode. When
this mode is enabled, the ADT7311 immediately completes a
conversion and then goes into shutdown mode.
Wait for a minimum of 240 ms after writing to the operation
mode bits before reading back the temperature from the
temperature value register. This time ensures that the ADT7311
has time to power up and complete a conversion.
To obtain an updated temperature conversion, reset the Bit 6 to
0 and Bit 5 to 1 in the configuration register (0x01).
The one-shot mode is useful when one of the circuit design
priorities is to reduce power consumption.
Rev. 0 | Page 10 of 24
Drtr Sheet
ADT73ꢂꢂ
mode by writing 0 to Bit 6 and 0 to Bit 5 of the configuration
CT and INT Operation in One-Shot Mode
register (Register Address 0x01). The ADT7311 typically takes
1 ms (with a 0.1 ꢀF 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 ADT7311 even
when it is in shutdown mode. When the part is taken out of
shutdown mode, the internal clock is started and a conversion
is initiated.
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.
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 operation mode bits (Bit 5 and Bit 6 of
the configuration register, Register Address 0x01) resets the
INT pin.
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 ADT7311 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 tempera-
ture 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.
For the CT pin in comparator mode, if the temperature
drops below the TCRIT – THYST value, a write to the operation
mode bits (Bit 5 and Bit 6 of the configuration register,
Register Address 0x01) resets the CT pin (see Figure 13).
When using one-shot mode, ensure that the refresh rate is
appropriate to the application being used.
SHUTDOWN
The ADT7311 can be placed in shutdown mode by writing 1
to Bit 6 and 1 to Bit 5 of the configuration register (Register
Address 0x01). The ADT7311 can be taken out of shutdown
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
Rev. 0 | Page 11 of 24
ADT73ꢂꢂ
Drtr Sheet
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 ADT7311 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 is 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
10-Bit Temperature Data Format
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.
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 ADT7311 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
Temperature (Binary) Bits[1ꢀ:3]
Digital
Output (Hex)
where ADC Code uses all nine bits of the data byte, including
the sign bit.
−40°C
−25°C
−0.0625°C
0°C
+0.0625°C
+25°C
+50°C
+125°C
+150°C
1 1100 1110 0000
1 1110 0111 0000
1 1111 1111 1111
0 0000 0000 0000
0 0000 0000 0001
0 0001 1001 0000
0 0011 0010 0000
0 0111 1101 0000
0 1001 0110 0000
0x1CE0
0x1E70
0x1FFF
0x000
0x001
0x190
0x320
0x7D0
0x960
Negative Temperature = ADC Code(dec) – 256
where the MSB is removed from the ADC code.
Rev. 0 | Page 12 of 24
Drtr Sheet
ADT73ꢂꢂ
REGISTERS
STATUS REGISTER
The ADT7311 contains eight registers:
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 tempera-
•
•
•
•
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
ture limits including hysteresis. The
from the temperature value register. In one-shot and 1 SPS modes,
RDY
bit is reset after a read
Table 6. ADT7311 Registers
the
bit is reset after a write to the operation mode bits.
Register
Address Description
Power-On
Default
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
Status
0xꢀ0
0x00
0x0000
0xC3
0x49ꢀ0 (147°C)
0x05 (5°C)
0x2000 (64°C)
0x0500 (10°C)
Configuration
Temperature value
ID
TCRIT setpoint
THYST setpoint
THIGH setpoint
TLOW setpoint
Table 7. Status Register (Register Address 0x00)
Default
Bit
[3:0]
4
Value
0000
0
Type Name
Description
R
R
Unused Reads back 0.
TLOW
THIGH
TCRIT
RDY
This bit is set to 1 when the temperature goes below the TLOW temperature limit. The bit clears to 0
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
0
0
1
R
R
R
This bit is set to 1 when the temperature rises above the THIGH temperature limit. The bit clears to 0
when the status register is read and/or when the temperature measured drops below the limit set
in the THIGH − THYST setpoint registers.
This bit is set to 1 when the temperature rises above the TCRIT temperature limit. This bit clears to 0
when the status register is read and/or when the temperature measured drops 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 operation mode bits.
Rev. 0 | Page 13 of 24
ADT73ꢂꢂ
Drtr Sheet
CONFIGURATION REGISTER
continuous conversion, interrupt pins polarity, and
overtemperature fault queues.
This 8-bit read/write register (Register Address 0x01) stores various
configuration modes for the ADT7311, including shutdown,
overtemperature and undertemperature interrupts, one-shot,
Table 8. Configuration Register (Register Address 0x01)
Default
Value
Bit
Type Name
Description
[1:0]
00
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.
00 = 1 fault (default).
01 = 2 faults.
10 = 3 faults.
11 = 4 faults.
2
0
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.
0 = active low.
1 = active high.
3
0
This bit selects the output polarity of the INT pin.
0 = active low.
1 = active high.
4
0
This bit selects between comparator mode and interrupt mode.
0 = interrupt mode.
1 = comparator mode.
[6:5]
00
Operation mode These two bits set the operational mode for the ADT7311.
00 = continuous conversion (default). When one conversion is finished, the ADT7311
starts another.
01 = one shot. Conversion time is typically 240 ms.
10 = 1 SPS mode. Conversion time is typically 60 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
0
R/W
Resolution
0 = 13-bit resolution. Sign bit + 12 bits gives a temperature resolution of 0.0625°C.
1 = 16-bit resolution. Sign bit + 15 bits gives a temperature resolution of 0.007ꢀ°C.
Rev. 0 | Page 14 of 24
Drtr Sheet
ADT73ꢂꢂ
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 tempera-
ture 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
0
0
R
TLOW flag/LSB0
Flags a TLOW event if the configuration register, Register Address 0x01[7] = 0
(13-bit resolution). When the temperature value is below TLOW, this bit it set to 1.
Contains the Least Significant Bit 0 of the 15-bit temperature value if the
configuration register, Register Address 0x01[7] = 1 (16-bit resolution).
1
2
0
0
R
R
THIGH flag/LSB1
TCRIT flag/LSB2
Flags a THIGH event if the configuration register, Register Address 0x01[7] = 0
(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 0x01[7] = 1 (16-bit resolution).
Flags a TCRIT event if the configuration register, Register Address 0x01[7] = 0
(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 0x01[7] = 1 (16-bit resolution).
[7:3]
[14:ꢀ]
15
00000
0000000
0
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
[2:0]
[7:3]
011
R
R
Revision ID
Manufacturer ID
Contains the silicon revision identification number.
Contains the manufacturer identification number.
11000
Table 11. TCRIT Setpoint Register (Register Address 0x04)
Bit
Default Value
Type
Name
Description
[15:0]
0x49ꢀ0
R/W
TCRIT
16-bit critical overtemperature limit, stored in twos complement format.
Rev. 0 | Page 15 of 24
ADT73ꢂꢂ
Drtr Sheet
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.
THYST SETPOINT REGISTER
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
The default setting for the THIGH setpoint is 64°C.
TLOW 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.
TLOW value to implement hysteresis.
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
The default setting for the TLOW setpoint is 10°C.
Table 12. THYST Setpoint Register (Register Address 0x05)
Bit
Default Value Type Name Description
[3:0]
[7:4]
0101
0000
R/W
R/W
THYST
N/A
Hysteresis value, from 0°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
[15:0]
0x2000
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
[15:0]
0x0500
R/W
TLOW
16-bit undertemperature limit, stored in twos complement format.
Rev. 0 | Page 16 of 24
Drtr Sheet
ADT73ꢂꢂ
SERIAL PERIPHERAL INTERFA°E
PULL-UP
V
V
DD
DD
V
10kΩ 10kΩ
DD
0.1µF
ADT7311
GND
CT
SCLK
DOUT
DIN
MICROCONTROLLER
INT
CS
Figure 14. Typical SPI Interface Connection
The ADT7311 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
Bit C7, Bit C2, Bit C1, and Bit C0 of the command byte must all
be set to 0 to successfully begin a bus transaction. The SPI
interface does not work correctly if a 1 is written into any of
these bits.
CS
and out of the device. A chip select pin ( ) enables or disables
Bit C6 is the read/write bit; 1 indicates a read, and 0 indicates
a write.
CS
the serial interface.
is required for correct operation of the
interface. Data is clocked out of the ADT7311 on the negative
edge of SCLK, and data is clocked into the device on the
positive edge of SCLK.
Bits[C5:C3] contain the target register address. One register can
be read from or written to per bus transaction.
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 ADT7311 whether the transaction is a read or
a write and provides the address of the register for the data
transfer. Table 15 shows the format of the command byte.
Table 15. Command Byte
C7
C6
Cꢀ
C4
C3
C2
C1
C0
0
R/W
Register address
0
0
0
Rev. 0 | Page 17 of 24
ADT73ꢂꢂ
Drtr Sheet
Figure 15 shows a write to an 8-bit register, and Figure 16 shows
a write to a 16-bit register.
WRITING DATA
Data is written to the ADT7311 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 ADT7311 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
0
0
0
0
R/W REGISTER ADDR
C4
C0
D7
D6
D5
D4
D3
D2
D1
D0
C3
C1
C6
C5
C2
C7
DIN
Figure 15. 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
0
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 16. Writing to a 16-Bit Register
Rev. 0 | Page 1ꢀ of 24
Data Sheet
ADT7311
CS
can be tied to ground, and the serial interface can be
READING DATA
operated in a 3-wire mode. DIN, DOUT, and SCLK are
used to communicate with the ADT7311 in this mode.
A read transaction begins when the master writes the command
byte to the ADT7311 with the read/write bit set to 1. The master
then supplies eight or 16 clock pulses, depending on the addressed
register, and the ADT7311 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.
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 ADT7311 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 opera-
tion 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.
CS
The read transaction finishes when the master takes high.
INTERFACING TO DSPs OR MICROCONTROLLERS
CS
The ADT7311 can be operated with
chronization signal. This scheme is useful for DSP interfaces.
CS
used as a frame syn-
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 specifications in Table 2 are obeyed.
CS
SCLK
4
2
3
5
7
8
9
11
12
13
14
15
16
1
6
10
8-BIT COMMAND WORD
0
0
0
0
R/W REGISTER ADDR
DIN
C3
C1
C0
C5
C2
C4
C7
C6
8-BIT DATA
D5 D3
DOUT
D7
D6
D2
D1
D0
D4
Figure 17. Reading from an 8-Bit Register
CS
SCLK
23
22
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
24
8-BIT COMMAND BYTE
0
0
0
R/W
C6
REGISTER ADDR
C4
0
DIN
C0
C3
C1
C5
C2
C7
16-BIT DATA
D9
D8
D1
D0
DOUT
D12
D10
D7
D2
D15
D14
D13
D11
Figure 18. Reading from a 16-Bit Register
Rev. 0 | Page 19 of 24
ADT73ꢂꢂ
Drtr Sheet
INT AND °T OUTPUTS
Comparator Mode
The INT and CT pins are open-drain outputs, and both pins
require a 10 kΩ pull-up resistor to VDD. The ADT7311 must be
fully powered up to VDD before reading INT and CT data.
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 ADT7311 into shutdown mode does not reset the
INT state in comparator mode.
The INT and CT pins have two undertemperature/over-
temperature modes: comparator mode and interrupt mode.
The interrupt mode is the default power-up overtemperature
mode. The INT output pin becomes active when the tempera-
ture 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 ADT7311
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.
Placing the ADT7311 into shutdown mode resets the INT pin
in the interrupt mode.
Figure 19 illustrates the comparator and interrupt modes for
events exceeding the THIGH limit with both pin polarity settings.
Figure 20 illustrates the comparator and interrupt modes for
events exceeding the TLOW limit with both pin polarity settings.
TEMPERATURE
82°C
81°C
80°C
79°C
78°C
77°C
76°C
75°C
74°C
73°C
THIGH
THIGH – THYST
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 19. INT Output Temperature Response Diagram for THIGH Overtemperature Events
Rev. 0 | Page 20 of 24
Drtr Sheet
ADT73ꢂꢂ
TEMPERATURE
–13°C
–14°C
–15°C
–16°C
–17°C
–18°C
–19°C
–20°C
–21°C
–22°C
T
LOW + THYST
TLOW
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 TLOW Undertemperature Events
Rev. 0 | Page 21 of 24
ADT73ꢂꢂ
Drtr Sheet
APPLI°ATIONS INFORMATION
ADT7311 operates within specification. The RC filter should be
mounted as far away as possible from the ADT7311 to ensure
that the thermal mass is kept as low as possible. For additional
information, contact Analog Devices.
THERMAL RESPONSE TIME
Thermal response is a function of the thermal mass of the
temperature sensor, but it is also heavily influenced by the mass
of the object the IC is mounted to. For example, a large PCB
containing large amounts of copper tracking can act as a large
heat sink and slow the thermal response. For a faster thermal
response, it is recommended to mount the sensor on as small a
PCB as possible.
TEMPERATURE MONITORING
The ADT7311 is ideal for monitoring the thermal environment
within hazardous automotive applications. The die accurately
reflects the thermal conditions that affect nearby integrated
circuits.
SUPPLY DECOUPLING
The ADT7311 must have a decoupling capacitor connected
between VDD and GND; otherwise, incorrect temperature
readings will be obtained. A 0.1 ꢀF decoupling capacitor, such
as a high frequency ceramic type, must be used and mounted as
close as possible to the VDD pin of the ADT7311.
The ADT7311 measures and converts the temperature at the
surface of its own semiconductor chip. When the ADT7311 is
used to measure the temperature of a nearby heat source, the
thermal impedance between the heat source and the ADT7311
must be considered.
If possible, the ADT7311 should be powered directly from the
system power supply. This arrangement, shown in Figure 21,
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 ꢀF ceramic capacitor is
critical for the temperature accuracy specifications to be
achieved.
When the thermal impedance is determined, the temperature
of the heat source can be inferred from the ADT7311 output.
As much as 60% of the heat transferred from the heat source to
the thermal sensor on the ADT7311 die is discharged via the
copper tracks and the bond pads. Of the pads on the ADT7311,
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 ADT7311 GND pad and the
GND of the heat source be reduced as much as possible.
TTL/CMOS
LOGIC
QUICK GUIDE TO MEASURING TEMPERATURE
CIRCUITS
0.1µF
ADT7311
1. After power-up, reset the serial interface (load 32 consecutive
1s on DIN). This ensures all internal circuitary is properly
initialized.
2. Verify the setup by reading the device ID (Register Address
POWER
SUPPLY
0x03). It should read 0xC3.
3. After consistent consecutive readings are obtained from
Step 2, proceed to read the configuration register (0x01),
Figure 21. Use of Separate Traces to Reduce Power Supply Noise
POWERING FROM A SWITCHING REGULATOR
TCRIT (0x04), THIGH (0x06), and TLOW (0x07). Compare to
the specified defaults in Table 6. If all the readings match,
the interface is operational.
4. Write to the configuration register to set theADT7311 to
the desired configuration. Read the temperature value
register. It should produce a valid temperature measurement.
Precision analog devices such as the ADT7311 require a well-
filtered power source. If the ADT7311 is powered from a
switching regulator, noise may be generated in the 50 kHz to
3 MHz range that may affect the temperature accuracy specifica-
tion. To prevent this, it is recommended to connect an RC filter
between the power supply and VDD. The value of components
used should be carefully considered to ensure that the
Rev. 0 | Page 22 of 24
Drtr Sheet
ADT73ꢂꢂ
OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
8
1
5
4
6.20 (0.2441)
5.80 (0.2284)
4.00 (0.1574)
3.80 (0.1497)
0.50 (0.0196)
0.25 (0.0099)
1.27 (0.0500)
BSC
45°
1.75 (0.0688)
1.35 (0.0532)
0.25 (0.0098)
0.10 (0.0040)
8°
0°
0.51 (0.0201)
0.31 (0.0122)
COPLANARITY
0.10
1.27 (0.0500)
0.40 (0.0157)
0.25 (0.0098)
0.17 (0.0067)
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MS-012-AA
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.
Figure 22. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
ORDERING GUIDE
Model1, 2
Temperature Range3
Temperature Accuracy4
Package Description
ꢀ-Lead SOIC_N
ꢀ-Lead SOIC_N
ꢀ-Lead SOIC_N
Evaluation Board
Package Option
ADT7311WTRZ
ADT7311WTRZ-RL
ADT7311WTRZ-RL7
EVAL-ADT7X10EBZ
–40°C to +150°C
–40°C to +150°C
–40°C to +150°C
0.5°C
0.5°C
0.5°C
R-ꢀ
R-ꢀ
R-ꢀ
1 Z = RoHS Compliant Part.
2 W = Qualified for Automotive Applications.
3 Operating at extended temperatures over prolonged periods depends on the lifetime performance of the part.
4 Maximum accuracy over the −40°C to +105°C temperature range (VDD = 2.7 V to 3.6 V)
AUTOMOTIVE PRODUCTS
The ADT7311W models are available with controlled manufacturing to support the quality and reliability requirements of automotive
applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers
should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in
automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to
obtain the specific Automotive Reliability reports for these models.
Rev. 0 | Page 23 of 24
ADT73ꢂꢂ
NOTES
Drtr Sheet
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D090ꢀ0-0-9/11(0)
Rev. 0 | Page 24 of 24
相关型号：
ADT7312WCZ-PT7
Automotive, ±1°C Accurate, 16-Bit, 175°C Digital SPI Temperature Sensor in Die Form
ADI
ADT7316
SPI/I2C Compatible, 10-Bit Digital Temperature Sensor and Quad Voltage Output 12/10/8-Bit DAC
ADI
ADT7316ARQ
SPI/I2C Compatible, 10-Bit Digital Temperature Sensor and Quad Voltage Output 12/10/8-Bit DAC
ADI
ADT7316ARQ
DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 5Cel, RECTANGULAR, SURFACE MOUNT, MO-137-AB, QSOP-16
ROCHESTER
ADT7316ARQ-REEL
DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 5Cel, RECTANGULAR, SURFACE MOUNT, MO-137-AB, QSOP-16
ROCHESTER
ADT7316ARQ-REEL7
DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 5Cel, RECTANGULAR, SURFACE MOUNT, MO-137-AB, QSOP-16
ROCHESTER
ADT7316ARQZ
DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 5Cel, RECTANGULAR, SURFACE MOUNT, LEAD FREE, MO-137-AB, QSOP-16
ROCHESTER
©2020 ICPDF网 联系我们和版权申明