HTU31D - Digital humidity- and temperature sensor by AMSYS

humidity-/temperature sensor HTU31D

The digital OEM sensor HTU31D is a combination of a capacitive humidity sensing element and temperature sensor. Each sensor is individually calibrated, compensated and tested. With this new series two different I2C addresses can be programmed.

The humidity can be measured within a range of 0 to 100 %RH. The temperature sensor is designed for a range of -40 to 125 °C. The typ. accuracy for humidity is ± 2 %RH in the measuring range of 20 – 100 %RH @25 °C and ±0.2 °C for temperature between 0 – 100 °C.

The I²C output signal for humidity and temperature fit for further data processing with simple, inexpensive microcontrollers. The resolution of the HTU31D can be set between 0.020 – 0.007 %RH for humidity and 0.040 – 0.012 °C for temperature. In addition, the sensor offers a diagnostic register that can be used to check whether the values for humidity and temperature are outside the specified range.

The typical power consumption for a measurement per second is approx. 3.78 µW with a 5 V supply @25 °C. Due to its low energy consumption, the sensor is suitable for battery operation.

The CRC check (Cyclic Redundancy Check) ensures secure data transmission. The humidity and temperature signal response time as well as the recovery time (after complete condensation) are within a range of a few seconds.

The HTU31D’s semiconductor components are mounted in a (reflow-) solderable 2.5 x 2.5 x 0.9 mm3 DFN chip package (dual-flat no-lead).


  • Humidity range: 0 – 100 %RH
  • Temperature range: -40 – 125 °C
  • Digital I2C interface
  • Alternative I2C address
  • I2C clock frequency up to 10 MHz
  • Accuracy: ±2 %RH
  • Supply voltage: 3 – 5.5 V
  • Fast response time
  • Programmable resolution
  • Fast recovering time after condensation
  • Electrical identification number
  • Low power consumption 3,78 μW
  • Small size (DFN-package)
  • RoHS and REACH compliant


  • Car cabins
  • Home appliance
  • Medical devices
  • Electrical devices
  • Humidifier / dehumidifier and drier
  • Building equipment
  • Weather stations
  • Security control devices
  • Multi-media devices (smartphone, tablet)

For information on prices and delivery times or if you have any technical questions, please contact