±0.5°C Accurate, 16-Bit Digital
www.BDTIC.com/ADI
SPI Temperature Sensor
Preliminary Technical Data
FEATURES
16-bit temperature-to-digital converter
Temperature accuracy ±0.5°C from 0°C to 70°C
SPI-compatible interface
Operating temperature from−55°C to +175°C
Operating voltage from 2.7 V to 5.5 V
Critical overtemperature indicator
Programmable overtemperature/undertemperature
interrupt
Shutdown mode for low power consumption
Power consumption: 1 mW typically at 3.3 V
8-lead narrow SOIC RoHS-compliant package
APPLICATIONS
Medical equipment
Isolated sensors
Environmental control systems
Computer thermal monitoring
Thermal protection
Industrial process control
Power system monitors
Hand-held applications
GENERAL DECSRIPTION
The ADT7310 is a high accuracy digital temperature sensor
in a standard narrow SOIC package. It contains a band gap
temperature sensor and a 13-bit ADC to monitor and digitize the
temperature to a resolution of 0.0625°C. The resolution can be
changed to 16 bits by setting a bit in the configuration register,
giving a 0.0078°C resolution. The default resolution is 13 bits.
The ADT7410 is guaranteed to operate at supply voltages from
2.7 V to 5.5 V. Operating at 3.3 V, the average supply current is
typically 250 A. The ADT7410 offers a shutdown mode that
powers down the device and gives a shutdown current of typically
0.8 A. The ADT7410 is rated for operation over the −55°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 80°C. The INT
pin is also an open-drain output that becomes active when the
temperature exceeds a programmable limit. The INT pin can
operate in either comparator or interrupt mode.
FUNCTIONAL BLOCK DIAGRAM
INTERNAL
OSCILLATOR
Σ-Δ
MODULATOR
FILTER
LOGIC
T
CRIT
REGISTER
T
HYST
REGISTER
Figure 1.
T
LOW
REGISTER
T
HIGH
REGISTER
T
CRIT
T
HIGH
T
LOW
SCLK
DOUT
DIN
CS
INTERNAL
REFERENCE
1
TEMPERATURE
2
3
4
SPI INTERFACE
SENSOR
ADT7312
CONFIGURATIO N &
STATUS REGIST ERS
TEMPERAT URE
VALUE
REGISTER
PRODUCT HIGHLIGHTS
An on-chip temperature sensor allows an accurate
measurement of the ambient temperature. The measurable
temperature range is −55°C to +150°C.
Supply voltage is 2.7 V to 5.5 V.
Available in an 8-lead narrow SOIC packag
Temperature accuracy is ±0.5°C max from 0°C to 70°C.
Default temperature resolution is 0.0625°C.
First conversion on power-up is a fast conversion to
ensure fast CT and INT pin activation in overtemperature
situations.
Programmable temperature interrupt limits.
Shutdown mode reduces the current consumption to
0.8 A typical.
ADT7310
6
CT
5
INT
7
GND
8
V
DD
06791-001
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
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Tel: 781.329.4700 www.analog.com
Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved.
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Decsription ......................................................................... 1
Product Highlights ........................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
SPI Timing Specifications ........................................................... 5
Absolute Maximum Ratings ............................................................ 6
ESD Caution .................................................................................. 6
Pin Configuration and Function Descriptions ............................. 7
Typical Performance Characteristics ............................................. 8
Theory of Operation ........................................................................ 9
Circuit Information ...................................................................... 9
Converter Details .......................................................................... 9
Temperature Measurement ......................................................... 9
One-Shot Mode .......................................................................... 10
Continuous Read Mode ............................................................. 11
Shutdown ..................................................................................... 11
Fault Queue ................................................................................. 11
Temperature Data Format ......................................................... 12
Registers ........................................................................................... 13
Serial Interface ................................................................................ 16
INT & CT Outputs ......................................................................... 18
INT Overtemperature Modes ................................................... 18
Application Information ................................................................ 20
Thermal Response Time ........................................................... 20
Supply Decoupling ..................................................................... 20
Temperature Monitoring ........................................................... 20
Outline Dimensions ....................................................................... 21
Ordering Guide .......................................................................... 21
REVISION HISTORY
11/07—Revision PrA: Preliminary Version A
Rev. PrA | Page 2 of 22
Preliminary Technical Data ADT7310
www.BDTIC.com/ADI
SPECIFICATIONS
TA = −55°C to +150°C; VCC = 2.7 V to 5.5 V; unless otherwise noted
Table 1.
Parameter Min Typ Max Unit Test Conditions/Comments
TEMPERATURE SENSOR AND ADC
Accuracy ±0.5 °C TA = 0°C to +70°C
±0.5 °C TA = -20°C to +100°C, VDD = 3.3 V
±1.5 °C TA = −40°C to +125°C
±2 °C TA = −55°C to +150°C
ADC Resolution 13 Bits
16 Bits
Temperature Resolution
13 Bits 0.0625 °C
16 Bits 0.0078125 °C
Temperature Conversion Time 240 ms
Fast Temperature Conversion Time 6 10 ms First conversion on power-up only
Fast One-Shot Conversion Time 60 ms Fast one-shot conversion mode
Fast Temperature Conversion
Accuracy
±TBD ±TBD °C TA = −40°C to +125°C
±TBD ±TBD °C TA = −55°C to +150°C
Long-Term Drift 0.08 °C Drift over 10 years, if part is operated at 55°C
Temperature Hysteresis 0.02 °C Temperature cycle = 25°C to 125°C, and back to 25°C
Repeatability 0.01 ? °C TA = +25°C
DC PSRR TBD °C/V TA = +25°C
DIGITAL OUTPUTS (OPEN DRAIN)
High Output Leakage Current, IOH 0.1 5 μA CT and INT pins pulled up to 5.5 V
Output High Current, I
Output Low Voltage, VOL 0.4 V IOL = 2 mA
Output High Voltage, VOH 0.7 × VDD V
Output Capacitance, C
RON Resistance (Low Output) 15 Ω Supply and temperature dependent
DIGITAL INPUTS
Input Current ±1 μA VIN = 0 V to VDD
Input Low Voltage, VIL 0.8 V
Input High Voltage, VIH 2.5 V
Pin Capacitance 10 pF
DIGITAL OUTPUT (DOUT)
Output High Voltage, VOH V
Output Low Voltage, V
Output Capacitance, C
POWER REQUIREMENTS
Supply Voltage 2.7 5.5 V
Supply Current at 3.3 V TBD TBD μA Peak current while converting ,SPI interface inactive
Supply Current at 5.0 V TBD 350 μA Peak current while converting ,SPI interface inactive
Shutdown Mode at 3.3 V TBD TBD μA Supply current in shutdown mode
Shutdown Mode at 5.0 V TBD 1 μA Supply current in shutdown mode
OH
OUT
OL
50 pF
OUT
±TBD ±TBD °C T
1 mA VOH = 5 V
3 10
− 0.3 V I
OH
0.4 V IOL = 200 μA
Twos complement temperature value of sign bit plus
12 ADC bits (power-up default resolution)
Twos complement temperature value of sign bit plus
15 ADC bits (D7 = 1 in the configuration register)
Continuous conversion mode and one-shot
conversion mode
= 0°C to +70°C
A
= I
SOURCE
= 200 μA
SINK
Rev. PrA | Page 3 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
Parameter Min Typ Max Unit Test Conditions/Comments
Power Dissipation TBD μW VDD = 3.3 V, normal mode at 25°C
1 Sample Per Second 150 μW Power dissipated for VDD = 3.3 V at 25°C
1 Sample Per Second 315 μW Power dissipated for VDD = 5.0 V at 25°C
Rev. PrA | Page 4 of 22
Preliminary Technical Data ADT7310
www.BDTIC.com/ADI
SPI TIMING SPECIFICATIONS
All input signals are specified with tR (rise time) = tF (fall time) = 5 ns (10% to 90% of VDD) and timed from a voltage level of 1.6 V.
T
= −55°C to +150°C, VDD = +2.7 V to +5.5 V, unless otherwise noted.
A
Table 2.
Parameter
t1 0 ns min
1, 2
Limit at T
, T
(B Version) Unit Conditions/Comments
MIN
MAX
falling edge to SCLK active edge setup time4
CS
t2 100 ns min SCLK high pulse width
t3 100 ns min SCLK low pulse width
t4 30 ns min Data valid to SCLK edge setup time
t5 25 ns min Data valid to SCLK edge hold time
3
t
0 ns min SCLK active edge to data valid delay4
6
60 ns max VDD = 4.5 V to 5.5 V
80 ns max VDD = 2.7 V to 3.6 V
5
t
10 ns min
7
Bus relinquish time after CS
inactive edge
80 ns max
t8 0 ns min
t9 0 ns min
rising edge to SCLK edge hold time
CS
falling edge to DOUT active time
CS
60 ns max VDD = 4.5 V to 5.5 V
80 ns max VDD = 2.7 V to 3.6 V
t10 10 ns min SCLK inactive edge to DOUT high
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
These numbers are measured with the load circuit shown in Figure 4 and defined as the time required for the output to cross the VOL or VOH limits.
4
SCLK active edge is falling edge of SCLK.
5
These numbers are derived from the measured time taken by the data output to change 0.5 V when loaded with the circuit shown in Figure 4. The measured number
is then extrapolated back to remove the effects of charging or discharging the 50 pF capacitor. 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
t
SCLK
DIN
DOUT
1
t
9
t
2
1
t
4
t
5
MSB LSB
t
3
23
Figure 2. Detailed SPI Timing Diagram
7
t
8
8
12
t
6
MSB
7
LSB
8
t
10
t
7
Rev. PrA | Page 5 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
VDD to GND –0.3 V to +7 V
SDA Input Voltage to GND –0.3 V to VDD + 0.3 V
SDA Output Voltage to GND –0.3 V to VDD + 0.3 V
SCL Input Voltage to GND –0.3 V to VDD + 0.3 V
CT and INT Output Voltage to GND –0.3 V to VDD + 0.3 V
Operating Temperature Range –55°C to +150°C
Storage Temperature Range –65°C to +160°C
Maximum Junction Temperature, T
150.7°C
JMAX
8-Lead N-SOIC (R-8)
Power Dissipation1 W
MAX
= (T
JMAX
− T
2
A
)/θJA
Thermal Impedance3
θJA, Junction-to-Ambient (Still Air) 157°C/W
θJC, Junction-to-Case 56°C/W
IR Reflow Soldering
Peak Temperature (RoHS-Compliant
260°C (+0°C)
Package)
Time at Peak Temperature 20 sec to 40 sec
Ramp-Up Rate 3°C/sec maximum
Ramp-Down Rate –6°C/sec maximum
Time from 25°C to Peak Temperature 8 minutes maximum
1
Values relate to package being used on a standard 2-layer PCB. This gives a
worst-case θJA and θJC. Refer to Figure 3 for a plot of maximum power
dissipation vs. ambient temperature (TA).
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.
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.
ESD CAUTION
I
(1.6mA WITH VDD = 5V,
SINK
100µA WIT H V
DD
Figure 3. SOIC_N Maximum Power Dissipation vs. Temperature
= 3V)
TO
OUTPUT
PIN
50pF
I
SOURCE
100µA WIT H V
Figure 4. Load Circuit for Timing Characterization
Rev. PrA | Page 6 of 22
1.6V
(200µA WIT H VDD = 5V,
= 3V)
DD
6791-002
Preliminary Technical Data ADT7310
D
www.BDTIC.com/ADI
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
SCLK
1
ADT7310
2
DOUT
DIN
TOPVIEW
(Not to Sca l e )
3
4
CS
Figure 5. Pin Configuration
8
V
DD
7
GN
6
CT
5
INT
Table 4. Pin Function Descriptions
Pin
Mnemonic Description
No.
1 SCLK
Serial Clock Input. The serial clock is used to clock in and clock out data to and from any register of
the ADT7310.
2 DOUT
3 DIN
SPI Serial Data Output. Data from the registers output from the part on DOUT pin . 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
CS
Chip Select Input. Logic Input. The device is selected when this input is low. The SCLK input is
disabled when this pin is high.
5 INT
Over temperature and Under temperature Indicator. Power-up default setting is as an active low
comparator interrupt. Open-drain configuration. Needs a pull-up resistor.
6 CT
Critical Over temperature Indicator. Power-up default polarity is active low. Open-drain
configuration. Needs a pull-up resistor.
7 GND Analog and Digital Ground.
8 VDD Positive Supply Voltage, 2.7 V to 5.5 V. The supply should be decoupled to ground.
Rev. PrA | Page 7 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 6. Temperature Accuracy of 40 ADT7310 Devices @ 3.3 V
Figure 7. Temperature Accuracy of 40 ADT7310 Devices @ 5 V
Figure 9. Operating Supply Current vs. Supply Voltage at 30°C
Figure 10. Shutdown Current vs. Supply Voltage at 30°C
Figure 8. Operating Supply Current vs. Temperature
Rev. PrA | Page 8 of 22
Figure 11. Temperature Accuracy vs. Supply Ripple Frequency (PSRR)
Preliminary Technical Data ADT7310
www.BDTIC.com/ADI
THEORY OF OPERATION
CIRCUIT INFORMATION
The ADT7310 is a 16-bit digital temperature sensor with the 16th
bit acting as the sign bit. An on-board temperature sensor generates
a voltage precisely proportional to absolute temperature, which is
compared to an internal voltage reference and input to a precision
digital modulator. Overall accuracy for the ADT7310 is ±1°C from
+130°C to +150°C. The serial interface is SPI compatible and the
open-drain outputs of the ADT7310 INT and CT pins are capable
of sinking 2 mA.
The on-board temperature sensor has excellent accuracy and
linearity over the entire rated temperature range without
needing correction or calibration by the user.
The sensor output is digitized by a ∑-∆ analog-to-digital
converter. This type of converter utilizes time-domain
oversampling and a high accuracy comparator to deliver 16 bits
of effective accuracy in an extremely compact circuit.
The measured temperature value is compared with a critical
temperature limit stored in the 16-bit T
a high temperature limit stored in the 16-bit T
register and a low temperature limit stored in the 16-bit T
read/write register,
CRIT
read/write
HIGH
LOW
read/write register. If the measured value exceeds these limits,
the INT pin is activated, and if it exceeds the T
limit, the CT
CRIT
pin is activated. The INT pin and the CT pin are programmable
for polarity via the configuration register while the INT pin is
also programmable for mode operation via the configuration
register.
Configuration register functions consist of
Switching between normal operation and full power-down.
Switching between comparator and interrupt event modes on
the INT pin.
Setting the CT and INT pins active polarity.
Setting the number of faults that activate the CT and
INT pins.
• Enabling the standard one-shot and fast one-shot mode.
CONVERTER DETAILS
The ∑-∆ 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.
The modulated output of the comparator is encoded using a
circuit technique that results in SPI temperature data.
Σ-Δ MODULATOR
VOLTAGE REF
AND VPTAT
CLOCK
GENERATOR
INTEGRATOR
Figure 12. ∑-∆ Modulator
COMPARATOR
1-BIT
DAC
LPF DIGITAL
FILTER
1-BIT
13-BIT
TEMPERATURE
VALUE
REGISTER
TEMPERATURE MEASUREMENT
In normal mode, the ADT7310 runs an automatic conversion
sequence. During this automatic conversion sequence, a
conversion takes 240 ms to complete and the ADT7310 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.
On power-up, the first conversion is a fast conversion, taking
typically 6 ms. Therefore, the CT and IN pins are activated very
quickly after power-up if an overtemperature event is present at
power-up.
The conversion clock for the part is generated internally.
No external clock is required except when reading from and
writing to the serial port.
In continuous conversion mode, the internal clock is reset after
every read or write operation. This causes the device to start a
temperature conversion after every read or write, the result of
which is typically available 240 ms later. Reading from the
device before a conversion is complete causes the ADT7310 to
finish converting and store the result in a shadow temperature
value register. The read operation provides the previous
conversion result. As soon as communication to the ADT7310
is complete, the result in the temporary temperature value
register is moved into the live temperature value register that
can be accessed by the SPI interface.
The measured temperature value is compared with a critical
temperature limit, stored in the 16-bit T
a high temperature limit, stored in the 16-bit T
register, and a low temperature limit, stored in the 16-bit T
read/write register. If the measured value exceeds these limits, the
INT pin is activated and if it exceeds the T
activated. This INT pin and the CT pin are programmable for
polarity via the configuration register while the INT pin is also
programmable for interrupt mode via the configuration register.
read/write register,
CRIT
read/write
HIGH
limit, the CT pin is
CRIT
LOW
06791-012
Rev. PrA | Page 9 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
ONE-SHOT MODE
Setting Bit 5 = 1 and Bit 6 = 0 of the configuration register
enables the one-shot mode. When this mode is enabled, the
ADT7310 immediately does a conversion and then goes into
shutdown mode. If a one-shot conversion is initiated at a rate
of one conversion per second, the current consumption is
reduced to typically TBD µA when V
when V
= 5 V.
DD
CS
= 3.3 V and TBD µA
DD
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 ADT7310 has time to
power up and do a conversion. This is shown in Figure 13.
The one-shot mode is useful when one of the circuit design
priorities is to reduce power consumption.
DIN
DOUT
SCLK
0x08 0x20
Figure 13. Typical SPI One-Shot Write to Configuration Register Followed by a Read from the Temperature Value Register
Fast One-Shot Mode
A fast one-shot mode reduces the conversion time to 60 ms
typically. The temperature accuracy is also reduced but this can
be compensated by greatly reduced current consumption. If a
fast one-shot conversion is initiated at a rate of one conversion
per second, the current consumption is reduced to typically
TBD µA when V
is 3.3 V and TBD µA when VDD is
DD
5 V. A fast one-shot temperature measurement is initiated when
the fast one-shot mode in the configuration register is initiated.
This is accomplished by writing Bit 5 = 0 and Bit 6 = 1. As soon
as Bit D5 and Bit D6 are set up for fast one-shot conversion, the
ADT7310 does a temperature conversion, and powers down.
CT & INT Operation in One-Shot Mode
Both the fast and standard one-shot temperature measurements
cause the INT and CT pins to go active if the temperature
exceeds their corresponding temperature limits. Therefore, it is
quite possible that the temperature can exceed the interrupt
limits for quite some time before a one-shot conversion is
activated. Refer to Figure 14 for more information on one-shot
CT pin operation for T
overtemperature events when one of
CRIT
the limits is exceeded.
Note that in interrupt mode, a read from any register resets the
INT pin after it is activated by a write to the standard or fast
one-shot bits. In the comparator mode, once the temperature
drops below the T
T
value, a write to the standard or fast one-shot bits resets
HYST
HIGH
– T
value or goes above the T
HYST
LOW
+
the INT pin, depending on which one-shot bit caused the
interrupt.
WAIT 240ms MINI MUM
FOR CONVERS ION TO F INISH
TEMPERATURE
148°C
147°C
146°C
145°C
144°C
143°C
142°C
141°C
140°C
139°C
CT PIN
POLARITY =
ACTIVE LOW
CT PIN
POLARITY =
ACTIVE HIGH
*THERE IS A 240ms DELAY BETWEEN W RITING T O THE
CONFI GURATI ON REGI STER T O 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 FAST ONE-SHOT
CONVERSION.
DATA
WRITE TO
D5 AND D6 OF
CONFIG URATION
REG.*
WRITE TO
D5 AND D6 OF
CONFIG URATION
Figure 14. One-Shot CT Pin
REG.*
WRITE TO
D5 AND D6 OF
CONFIG URATION
REG.*
T
T
HIGH
HIGH
TIME
– T
HYST
06791-015
06791-013
Rev. PrA | Page 10 of 22
Preliminary Technical Data ADT7310
www.BDTIC.com/ADI
CONTINUOUS READ MODE
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. Simply sending
16 SCLK clocks to the ADT7310 clocks the contents of the
temperature value register onto the DOUT pin.
To exit the continuous read mode, the command byte 01010000
(0x50) must be written to the ADT7310.
While in continuous read mode, the part monitors activity on
the DIN line so that it can receive the instruction to exit the
CS
continuous read mode. Additionally, a reset occurs if 32
consecutive 1s are seen on the DIN pin. Therefore, DIN should
be held low in continuous read mode until an instruction is to
be written to the device.
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 0’s are read. This is because the continuous
read mode blocks read access to temperature value register
during a conversion.
DIN
DOUT
SCLK
0x54
TEMPERATURE
VAL UE
Figure 15. Continuous Read Mode
SHUTDOWN
The ADT7310 can be placed in shutdown mode via the
configuration register, in which case the entire IC is shut down
and no further conversions are initiated until the ADT7310 is
taken out of shutdown mode. The ADT7310 can be taken out of
shutdown mode by writing 00 to Bit 5 and Bit 6 in the
configuration register. The ADT7310 typically takes TBD ms to
come out of shutdown mode. The conversion result from the
last conversion prior to shutdown can still be read from the
ADT7310 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.
TEMPERATURE
VAL UE
TEMPERATURE
VAL UE
06791-015
FAULT QUEUE
Bit D0 and Bit D1 of the configuration register is used to set up
a fault queue. Up to four faults is provided to prevent false
tripping of the INT and CT pins when the ADT7310 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 back
to zero.
Rev. PrA | Page 11 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
TEMPERATURE DATA FORMAT
One LSB of the ADC corresponds to 0.0625°C. The ADC can
theoretically measure a temperature range of −256°C to +255°C,
but the ADT7310 is guaranteed to measure a low value
temperature limit of −55°C to a high value temperature limit of
+175°C. The temperature measurement result is stored in the
16-bit temperature value register. It is compared with the high
temperature limits stored in the T
T
setpoint register. The temperature measurement result is
HIGH
also compared with the low temperature limit stored in the T
setpoint register.
Temperature data in the temperature value register, the T
setpoint register, the T
setpoint register, and the T
HIGH
setpoint register is represented by a 13-bit twos complement
word. The MSB is the temperature sign bit. The three LSBs of
the temperature value, bits [2:0], on power-up default, are not
part of the temperature conversion result and are flag bits for
T
, T
CRIT
HIGH
and T
. Table 5 shows the 13-bit temperature data
LOW
format without Bit 0 to Bit 2.
The number of bits in the temperature data word can be
extended to 16 bits twos complement by setting bit 7 = 1 in the
configuration register. When using a 16-bit temperature data
value, the temperature value bits[2:0] are not used as flag bits
and are now the LSB bits of the temperature value. The poweron default setting is to have a 13-bit temperature data value.
Designers that use a 9-bit temperature data format can still
use the ADT7310 by ignoring the last four LSBs of the 13-bit
temperature value. These four LSBs are Bit D3 to Bit D6 in
Tabl e 5.
setpoint register and the
CRIT
LOW
CRIT
LOW
Table 5. 13-Bit Temperature Data Format
Te mp e ra tu r e
Digital Output (Binary)
D15 to D3
Digital Output
(Hex)
−55°C 1 1100 1001 0000 0x1C90
−50°C 1 1100 1110 0000 0x1CE0
−25°C 1 1110 0111 0000 0x1E70
−0.0625°C 1 1111 1111 1111 0x1FFF
0°C 0 0000 0000 0000 0x000
+0.0625°C 0 0000 0000 0001 0x001
+10°C 0 0000 1010 0000 0x0A0
+25°C 0 0001 1001 0000 0x190
+50°C 0 0011 0010 0000 0x320
+75°C 0 0100 1011 0000 0x4B0
+100°C 0 0110 0100 0000 0x640
+125°C 0 0111 1101 0000 0x7D0
+150°C 0 1001 0110 0000 0x960
+175°C 0 1010 1111 0000 0xAF0
Temperature Conversion Formulas
16-Bit Temperature Data Format
Positive Temperature = ADC Code(d)/128
1
Negative Temperature = (ADC Code(d)
Negative Temperature = (ADC Code(d)
− 65536)/128
2
– 32768)/128
13-Bit Temperature Data Format
Positive Temperature = ADC Code(d)/16
3
Negative Temperature = (ADC Code(d)
Negative Temperature = (ADC Code(d)
− 8192)/16
2
– 4096)/16
10-Bit Temperature Data Format
Positive Temperature = ADC Code(d)/2
Negative Temperature = (ADC Code(d)
Negative Temperature = (ADC Code(d)
4
– 1024)/2
2
– 512)/2
Rev. PrA | Page 12 of 22
9-Bit Temperature Data Format
Positive Temperature = ADC Code(d)
Negative Temperature = ADC Code(d)
Negative Temperature = ADC Code(d)
5
– 512
2
– 256
1
For ADC Code, use all 16 bits of the data byte, including the sign bit.
2
For ADC Code, MSB is removed from the ADC code.
3
For ADC Code, use all 13 bits of the data byte, including the sign bit.
4
For ADC Code, use all 10 bits of the data byte, including the sign bit.
5
For ADC Code, use all nine bits of the data byte, including the sign bit.
Preliminary Technical Data ADT7310
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REGISTERS
The ADT7310 contains eight registers:
• Five temperature registers
• One status register
• One ID register
• One configuration register
The status register, configuration register, the T
and the ID register are the only registers that are eight bits wide while the rest are 16 bits wide. The temperature value register, the status
register, and the ID register are read-only. Both a read and write can be performed on the rest of the registers. On power-up, the serial
interface address pointer, (command word bits [C5:C3]), is loaded with 0x00 and points to the status register.
Table 6. ADT7310 Registers
Address
[C5, C4, C3]
000 Status 0x80
001 Configuration 0x00
010 Temperature value 0x0000
011 ID 0x00
100 T
101 T
110 T
111 T
Status Register
This 8-bit read-only register reflects the status of the over temperature and under temperature 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 temperature limits, less the hysteresis value. The RDYB bit is
reset after a read from the temperature value register. In standard and fast one-shot modes, the RDYB bit is reset after a write to the oneshot bits.
register,
HYST
Description Power-On Default
0x4980 (+147°C)
CRIT
0x05 (5°C)
HYST
0x2000 (+64°C)
HIGH
0X0500 (+10°C)
LOW
Table 7. Status Register
Address Data Bit Default Value Type Name Description
000 [3:0] 000 R Unused Reads back 0
[4] 0 R T
[5] 0 R T
[6] 0 R T
LOW
HIGH
CRIT
[7] 1 R RDBY
Rev. PrA | Page 13 of 22
This bit is set to 1 when the temperature goes below the T
LOW
temperature limit. The bit is cleared to 0 when the status register is
read and/or when the temperature measured goes back above the
limit set in T
This bit is set to 1 when the temperature goes above the T
LOW
+ T
registers.
HYST
HIGH
temperature limit. The bit is cleared to 0 when the status register is
read and/or when the temperature measured goes back below the
limit set in T
This bit is set to 1when the temperature goes over the T
HIGH
− T
registers
HYST
CRIT
temperature limit. This bit clears to 0 when the status register is read
and/or when the temperature measured goes back below the limit set
− T
in T
CRIT
registers.
HYST
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 standard and fast one-shot
modes, this bit is reset after a write to the one-shot bits.
ADT7310 Preliminary Technical Data
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Configuration Register
This 8-bit read/write register stores various configuration modes for the ADT7310. These modes are shutdown, over temperature and
under temperature interrupts, one-shot, continuous conversion, interrupt pins polarity, and overtemperature fault queues .
Table 8. Configuration Register
Address Data Bit Default Value Type Name Description
001 [1:0] 00
[2] 0
[3] 0
[4] 0
[6:5] 00
[7] 0
Temperature Value Register
This 16-bit read-only register stores the temperature measured by the internal temperature sensor. The temperature is stored in twos
complement format with the MSB being the temperature sign bit. When reading from this register, the MSBs are clocked out first. Bit D0
to Bit D2 are event alarm flags for T
CRIT
, T
then D0 to D2 are no longer used as flag bits and are instead used as the LSB bits for the extended digital value.
Fault
R/W
CT pin
R/W
INT pin
R/W
R/W
Operation
R/W
R/W
, and T
HIGH
These two bits set the number of overtemperature faults that occur
queue
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
This bit selects the output polarity of the CT pin.
polarity
0 = active low; 1 = active high.
This bit selects the output polarity of the INT pin.
polarity
0 = active low; 1 = active high.
INT mode This bit selects between comparator and interrupt mode.
0 = comparator mode; 1 = interrupt mode
These two bits set the operational mode for the ADT7310.
mode
00 = continuous conversion (default). Once one conversion is finished,
the ADT7310 starts another
01 = One shot. Conversion time is typically 240 ms
10 = Fast one shot. Conversion time is typically 60 ms. This operational
mode reduces the average current consumption even more so than
the standard one-shot mode
11= Shutdown. All circuitry except interface circuitry is powered down
Resolution This bit sets up the resolution of the ADC when converting.
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 0.0078125°C
. When the ADC is configured to convert the temperature to a 15-bit digital value
LOW
Table 9. Temperature Value Register
Address Data Bit Default Value Type Name Description
010 [0] 0 R T
Flag/ LSB0
LOW
Flags T
1. Flag clears to 0 when
If Configuration register[7] = 1, this contains the LSB of the 15 bit
temperature value
[1] 0 R T
Flag/ LSB1
HIGH
Flags T
1. Flag clears to 0 when
If Configuration register[7] = 1, this contains the LSB of the 15 bit
temperature value
[2] 0 R T
Flag/LSB2
CRIT
Flags T
1. Flag clears to 0 when
If Configuration register[7] = 1, this contains the LSB of the 15 bit
temperature value
[14:3] 0 R Temp Temperature Value in 2s complement format
[15] 0 R Sign Sign Bit. Indicates if temperature value is negative or positive
Rev. PrA | Page 14 of 22
event. While temperature value is below T
LOW
event. While temperature value is below T
LOW
event. While temperature value is below T
LOW
, this bit is set to
LOW
, this bit is set to
LOW
, this bit is set to
LOW
Preliminary Technical Data ADT7310
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Manufacturer ID Register
This 8-bit read-only register stores the manufacturer ID in Bit D3 to Bit D7 and the silicon revision in Bit D0 to Bit D2
Table 10. Manufacturer ID Register
Address Data Bit Default Value Type Name Description
011 [2:0] ?000 R Rev ID Contains the silicon revision identification number
[7:3] 11000 R Man ID Contains the manufacturer identification number
T
Setpoint Register
CRIT
This 16-bit read/write register stores the critical over temperature limit value. A critical over temperature 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 over
temperature event occurs The temperature is stored in twos complement format with the MSB being the temperature sign bit. When
reading from this register, the MSBs are clocked out first.
Table 11. T
Setpoint Register
CRIT
Address Data Bit Default Value Type Name Description
100 [15:0] 0x4900
R/W
T
CRIT
Critical over temperature limit, stored in 2’s complement format. The
default setting is +147°C
T
Setpoint Register
HYST
This 8-bit read/write register stores the temperature hysteresis value for the T
HIGH
, T
LOW
, and T
temperature limits. The temperature
CRIT
hysteresis value is stored in straight binary format using the four LSBs. Increments are possible in steps of 1°C from 0°C to +15°C. The
value in this register is added to the T
Table 12. T
Setpoint Register
HYST
HIGH
and T
values, and subtracted from the T
CRIT
value, to implement hysteresis,
LOW
Address Data Bit Default Value Type Name Description
101 [3:0] 0x5
R/W
T
HYST
Hysteresis value ,from0°C to +15°C. Stored in straight binary format.
The default setting is 5°C
[7: X
R/W
N/A Not Used
T
Setpoint Register
HIGH
This 16-bit read/write register stores the over temperature limit value. An over temperature 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 over temperature event
occurs The temperature is stored in twos complement format with the MSB being the temperature sign bit. When reading from this
register, the MSBs are clocked out first.
Table 13. T
Setpoint Register
HIGH
Address Data Bit Default Value Type Name Description
110 [15:0] 0x2000
R/W
T
HIGH
Over temperature limit, stored in 2’s complement format. The default
setting is +64°C
T
Setpoint Register
LOW
This 16-bit read/write register stores the under temperature limit value. An under temperature 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 under temperature event
occurs. The temperature is stored in twos complement format with the MSB being the temperature sign bit. When reading from this
register, the MSBs are clocked out first. The default setting has the T
limit at 10°C.
LOW
Table 14. T
Setpoint Register
LOW
Address Data Bit Default Value Type Name Description
111 [15:0] 0x0500
R/W
T
LOW
Rev. PrA | Page 15 of 22
Under temperature limit, stored in 2’s complement format. The default
setting is +10C
ADT7310 Preliminary Technical Data
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SERIAL INTERFACE
The ADT7310 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 the device. A chip select pin (
the serial interface.
CS
is required for correct operation of the
interface. Data is clocked out of the AD7T7312 on the negative
edge of SCLK, and data is clocked into the device on the
positive edge of SCLK.
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 ADT7310 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 C5 C4 C3 C2 C1 C0
0
R/W
Register Address
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
) enables or disables
Continuous
read
0 0
Bits [C5:C3] contain the target register address. You can only
read or write to one register per bus transaction.
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 ADT7310 clocks the
contents of the temperature value register onto the DOUT pin.
See Error! Reference source not found. section for more
information.
Writing Data
Data is written to the ADT7310 in 8 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
ADT7310 clocks the data into the register addressed in the
command byte on the positive edge of SCLK. The master
finishes the write by pulling
CS
high.
Figure 16 shows a write to an 8-bit register, and Figure 17 shows
a write to a 16-bit register.
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
SCLK
DIN
CS
SCLK
DIN
1234
8-BIT COMMAND BYTE
0
R/W REGISTER ADDR
C6
C7
1234
8-BIT COMMAND BYTE
0
R/W REGISTER ADDR
C4
C5
C6
C7
5 6 7 8 9 10111213141516
D5
D10
8-BIT DATA
D4
D11
CONT
0
C1
D7
0
C0
D14
D7
D13
D6
D12
READ
C4
C3
C5
5246 7 8 9 10 11 12 13 14 15 16
CONT
READ
C3
C2
C2
Figure 16. Writing to an 8-bit Register
0
0
C0
C1
Figure 17. Writing to a 16-bit Register
D3
D2
16-BIT DATA
D9
D8
D7
D1
D0
17
22 23
D2 D1
D0
Rev. PrA | Page 16 of 22
Preliminary Technical Data ADT7310
www.BDTIC.com/ADI
Reading Data
A read transaction begins when the master writes the command
byte to the ADT7310 with the read/write bit set to 1. The master
then supplies 8 or 16 clock pulses, depending on the addressed
register, and the ADT7310 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
The read transaction finishes when the master takes
The master must begin a new read transaction on the bus , for
every register read. Only one register is read from per bus
transaction However, in continuous read mode, Command
Byte[C2] =1, 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.
CS
high.
CS
SCLK
DIN
DOUT
SCLK
DIN
DOUT
1234
8-BIT COMMAND BYTE
0
R/W REGISTER ADDR
C6
C7
1234
8-BIT COMMAND WORD
0
R/W REGISTER ADDR
C4
C5
C6
C7
5246 7 8 9 10 11 12 13 14 15 16
CONT
READ
C4
C3
C5
C2
5 6 7 8 9 10111213141516
CONT
READ
C3
C2
Figure 18/ Read from an 8-bit Register
0
0
C0
C1
D15
Figure 19. Read from a 16-bit Register
Interfacing to DSPs or Microcontrollers
The ADT7412 can be operated with CS used as a frame
synchronization signal. This scheme is useful for DSP
interfaces. In this case, the first bit (MSB) is effectively clocked
CS
out by
, because CS normally occurs after the falling edge of
SCLK in DSPs. SCLK can continue to run between data
transfers, provided the timing numbers are obeyed
CS
can be tied to ground, and the serial interface operated in a
3-wire mode. DIN, DOUT and SCLK are used to communicate
with the ADT7310 in this mode.
For microcontroller interfaces, it is recommended that SCLK
idles high between data transfers.
C1
0
D14
0
C0
8-BIT DATA
D0
D1
D2
17
22 23
D2
D1
D13
D7
D12
D6
D11
D5
16-BIT DATA
D10
D9
D4
D3
D8 D7
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 ADT7310 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.
D0
Rev. PrA | Page 17 of 22
ADT7310 Preliminary Technical Data
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INT & CT OUTPUTS
The INT and CT pins are open drain, and require a pull-up
resistor to Vcc .By default, these outputs operate as active low. It
is possible to change them to active high operation by writing to
the configuration register bit 2 for the CT pin , and bit 3 for the
INT pin. Note that, when operated in active high mode, the CT
and INT pins should be pull-up to V
for example 50k, to minimize current drain.
INT OVERTEMPERATURE MODES
The ADT7310 INT pin has two temperature interrupt modes,
comparator mode and interrupt mode. The comparator 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 T
the temperature stored in the T
pin reacts after this event depends on the overtemperature
mode selected.
Figure 20 illustrates the comparator and interrupt modes for
events exceeding the T
limit with both pin polarity settings.
HIGH
through a large resistor,
CC
setpoint register or less than
HIGH
setpoint register. How this
LOW
TEMPERATURE
82°C
81°C
80°C
79°C
78°C
77°C
76°C
75°C
74°C
73°C
Figure 21 illustrates the comparator and interrupt modes for
events exceeding the T
limit with both pin polarity settings.
LOW
Comparator Mode
In comparator mode, the INT pin returns to its inactive status
when the temperature measured drops below the
− T
T
HIGH
limit or rises above the T
HYST
LOW
+ T
HYST
limit.
Putting the ADT7310 into shutdown mode does not reset the
INT state in comparator mode.
Interrupt Mode
In interrupt mode, the INT pin goes inactive when any ADT7310
register is read. Once the INT pin is reset, it goes active again
only when the temperature is greater than the temperature
stored in the T
stored in the T
setpoint register or less than the temperature
HIGH
setpoint register.
LOW
Placing the ADT7310 into shutdown mode resets the INT pin
in the interrupt mode.
T
HIGH
T
–T
HIGH
HYST
(COMPARATOR MODE)
POLARITY = ACTIVE LO W
(INTERRUPT MODE)
POLARITY = ACTIVE LO W
(COMPARATOR MODE)
POLARITY = ACTIVE HIGH
(INTERRUPT MODE)
POLARITY = ACTIVE HIGH
Figure 20. INT Output Temperature Response Diagram for T
INT PIN
INT PIN
INT PIN
INT PIN
READ
READ READ
Overtemperature Events
HIGH
TIME
06791-016
Rev. PrA | Page 18 of 22
Preliminary Technical Data ADT7310
R
A
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(COMPARATOR MODE)
POLARITY = ACTIVE LO W
(INTERRUPT MODE)
POLARITY = ACTIVE LO W
(COMPARATOR MODE)
POLARI TY = ACTIVE HIGH
(INTERRUPT MODE)
POLARI TY = ACTIVE HIGH
TEMPE
–13°C
–14°C
–15°C
–16°C
–17°C
–18°C
–19°C
–20°C
–21°C
–22°C
INT PIN
INT PIN
INT PIN
INT PIN
TURE
T
+T
LOW
HYST
T
LOW
TIME
READ
READ READ
Figure 21. INT Output Temperature Response Diagram for T
Overtemperature Events
LOW
06791-017
Rev. PrA | Page 19 of 22
ADT7310 Preliminary Technical Data
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APPLICATION INFORMATION
THERMAL RESPONSE TIME
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. Thus, the time
required for the ADT7310 to settle to the desired accuracy
is dependent on the package selected, 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.
SUPPLY DECOUPLING
The ADT7310 should be decoupled with a 0.1 µF ceramic
capacitor between V
when the ADT7310 is mounted remotely from the power supply.
Precision analog products, such as the ADT7310, require a wellfiltered power source.
Because the ADT7310 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 ADT7310 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 ADT7310 V
and GND. This is particularly important
DD
pin.
DD
TEMPERATURE MONITORING
The ADT7310 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 ADT7310 measures and converts the temperature at the
surface of its own semiconductor chip. When the ADT7310 is
used to measure the temperature of a nearby heat source, the
thermal impedance between the heat source and the ADT7310
must be considered. Often, a thermocouple or other temperature sensor is used to measure the temperature of the source,
while the temperature is monitored by reading back from the
ADT7310 temperature value register.
Once the thermal impedance is determined, the temperature of
the heat source can be inferred from the ADT7310 output. As
much as 60% of the heat transferred from the heat source to the
thermal sensor on the ADT7310 die is discharged via the
copper tracks and the bond pads. Of the pads on the ADT7310,
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 ADT7310 GND pad and the
GND of the heat source is reduced as much as possible.
For example, use the unique properties of the ADT7310 to
monitor a high power dissipation microprocessor. The ADT7310
should be mounted as close as possible to the microprocessor
with wide track connection to the GND plane of the microprocessor. The ADT7310 produces a linear temperature output without
requiring any external characterization.
It is not recommended to operate the device at temperatures
between+125°C and +150°C for more than a total of 5000
hours. It is also not recommended to operate the device at
temperatures between +150°C and +175°C for more than 100
hours. Any exposure beyond these limits or above +175°C
affects device reliability.
TTL/CMOS
LOGIC
CIRCUITS
POWER
SUPPLY
Figure 22. Use Separate Traces to Reduce Power Supply Noise
0.1µF
ADT7312
Rev. PrA | Page 20 of 22
06791-018
Preliminary Technical Data ADT7310
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OUTLINE DIMENSIONS
5.00 (0.1968)
4.80 (0.1890)
4.00 (0.1574)
3.80 (0.1497)
85
6.20 (0.2440)
5.80 (0.2284)
41
1.27 (0.0500)
BSC
0.25 (0.0098)
0.10 (0.0040)
COPLANARITY
0.10
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
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MS-012-AA
1.75 (0.0688)
1.35 (0.0532)
0.51 (0.0201)
0.31 (0.0122)
0.25 (0.0098)
0.17 (0.0067)
0.50 (0.0196)
0.25 (0.0099)
8°
1.27 (0.0500)
0°
0.40 (0.0157)
× 45°
Figure 23. 8-Lead Standard Small Outline Package [SOIC_N]
(R-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model Temperature Range Temperature Accuracy1 Package Description Package Option
ADT7310Z2 –55°C to +125°C ±0.5°C 8-Lead SOIC_N R-8
1
Temperature accuracy is over the 0°C to +70°C temperature range.
2
Z = RoHS Compliant Part.
Rev. PrA | Page 21 of 22
ADT7310 Preliminary Technical Data
www.BDTIC.com/ADI
NOTES
©2008 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
PR07789-0-9/08(PrA)
Rev. PrA | Page 22 of 22
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