DHT22 Temperature and Humidity Sensor

Easy to use with Arduino library and supports 3.3v and 5v operation.

I used some of these DHT22 sensors to add temperature and humidity displays to my Raspberry Pi web cams. Couldn't be simpler, just three wires and the DHT22 Python library from Adafruit. Most vendors charge $8 to $10 for just the bare sensor, but these come on a PCB with mounting holes and a wired connector. The PCB has an I2C pull-up resistor and a decoupling cap, so it makes for a very clean solution.

At the same price as the sensor itself you have here the connector and the pull-up resistor - so you don't need to add one

The documentation linked on this page is conflicting and does not match the part provided. It seems following the instructions burnt out my sensor. Very disapointed ----------------------------------------------------------------------------------------------------- We are sorry to know you are having issues with the product. Our technical support will contact you soon.

This sensor works quite nicely out-of-the-box on a 5V Arduino, and the specs suggest that it should also be compatible with 3.3v systems. The only problem I have with it is that the humidity sensor is quite laggy. When moving it from high (~99%RH) humidity test chamber to a low (~38%RH) humidity area it takes close to 30 seconds for the reported humidity value to start decreasing, and several minutes for it to stabilize at the lower value. Moving from low to high humidify it updates much more quickly, taking 5-10 seconds for the output to stabalize. This is a lovely little sensor for anyone who doesn't need to measure rapid RH changes, it should be ideal for a 3D printer enclosure or greenhouse.