ADT7320 Datasheet, PDF (1/24 Pages) Analog Devices – ±0.25°C Accurate, 16-Bit Digital SPI Temperature Sensor

Preliminary Technical Data
FEATURES
Temperature accuracy ±0.25°C from −20°C to +105°C
13- or 16-bit user-selectable temperature-to-digital
converter
Low drift silicon temperature sensor
No temperature calibration/correction required by user
Power saving 1 sample per second (SPS) mode
Fast first conversion on power-up of 6 ms
SPI-compatible interface
Operating temperature from −40°C to +150°C
Operating voltage: 2.7 V to 5.5 V
Critical overtemperature indicator
Programmable overtemperature/undertemperature interrupt
Low power consumption: 700 μW typical at 3.3 V
Shutdown mode for lower power: 7 μW typical at 3.3 V
16-lead RoHS-compliant LFCSP package
APPLICATIONS
RTD and thermistor replacement
Medical equipment
Cold junction compensation
Industrial controls and test
Food transportation and storage
Environmental monitoring and HVAC
±0.25°C Accurate, 16-Bit
Digital SPI Temperature Sensor
ADT7320
GENERAL DESCRIPTION
The ADT7320 is a high accuracy digital temperature sensor
offering breakthrough performance over a wide industrial range,
housed in an LFCSP package. It contains a band gap temperature
reference and a 13-bit analog-to-digital converter (ADC) to
monitor and digitize the temperature to a 0.0625°C resolution.
The ADC resolution, by default, is set to 13 bits (0.0625°C).
This can be changed to 16 bits (0.0078°C) by setting Bit 7 in the
configuration register (Register Address 0x01).
The ADT7320 is guaranteed to operate over supply voltages from
2.7 V to 5.5 V. Operating at 3.3 V, the average supply current is
typically 210 μA. The ADT7320 has a shutdown mode that
powers down the device and offers a shutdown current of
typically 2 μA. The ADT7320 is rated for operation over the
−40°C to +150°C temperature range.
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.
SCLK ¹
DOUT ²
DIN ³
CS ⁴
TEMPERATURE
VALUE
REGISTER
T_HYST
REGISTER
T_HIGH
REGISTER
FUNCTIONAL BLOCK DIAGRAM
INTERNAL
REFERENCE
INTERNAL
OSCILLATOR
CONFIGURATION
AND STATUS
REGISTERS
TEMPERATURE
SENSOR
T_CRIT
REGISTER
T_LOW
REGISTER
Σ-Δ
MODULATOR
FILTER
LOGIC
Figure 1.
ADT7320
T_CRIT
T_HIGH
6 CT
5 INT
T_LOW
7 GND
8 V_DD
Rev. PrA
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