The DHT22 is a temperature and humidity sensor. It is the successor of DHT11 only it provides more accurate data but also cost more in the acquisition.

The sensor operates with 3 pins. VCC, GND and Data, but Data isn’t an analog signal. It’s a digital signal which is working like 1Wire but is not compatible to it. You have to write your own library with the protocol of the DHT22 which can be found in the internet.


  • Minimal data-polling of 2 seconds
  • Non Dallas 1-Wire compatible
  • More accurate than DHT11
  • 3-5Volt
  • 2,5mA maximum current
  • 4 Pins
  • 2,4g weight
  • 0-100% relative humidity (2-5% accuracy)
  • Temperature range of -40 bis 80° degrees (+/- 0,5° degrees)