ADT7420 ±0.25°C Accurate, 16-Bit Digital I2C Temperature Sensor

Pin A0 and Pin A1 are available for address selection, giving the ADT7420 four possible I2C addresses. The CT pin is an open-drain output that becomes active when the temperature exceeds a programmable critical temperature limit. The INT pin is also an open-drain output that becomes active when the tempera-ture exceeds a programmable limit. The INT pin and CT pin can operate in comparator and interrupt event modes. Product Highlights Ease of use, no calibration or correction required by the user. Low power consumption. Excellent long-term stability and reliability. High accuracy for industrial, instrumentation, and medical applications. Packaged in a 16-lead, 4 mm × 4 mm LFCSP RoHS-compliant package. Applications RTD and thermistor replacement Cold junction compensation Medical equipment Industrial control and test Food transportation and storage Environmental monitoring and HVAC Laser diode temperature control

The ADT7420 is a high accuracy digital temperature sensor offering breakthrough performance over a wide industrial range, housed in a 4 mm × 4 mm LFCSP package. It contains an internal band gap reference, a temperature sensor, and a 16-bit ADC to monitor and digitize the temperature to 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.

The ADT7420 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 typi-cally 210 μA. The ADT7420 has a shutdown mode that powers down the device and offers a shutdown current of typically 2.0 μA at 3.3 V. The ADT7420 is rated for operation over the −40°C to +150°C temperature range.

Features and Benefits

Temperature accuracy:
±0.20°C from −10°C to +85°C
at 3.0 V
±0.25°C from −20°C to +105°C from 2.7 V to 3.3 V
16-bit resolution: 0.0078°C
Ultralow temperature drift:
0.0073°C
NIST traceable or equivalent
Fast first temperature conversion on power-up of 6 ms

Easy implementation
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
See data sheet for additonal features