The DHT22 is an affordable digital sensor that accurately measures temperature and humidity. It features a capacitive humidity sensor and a thermistor to sense the surrounding air and provides a digital output on the data pin, eliminating the need for analog input pins. It's easy to use, but you need to be precise with the timing when retrieving data. The main limitation is that you can only get new data every 2 seconds, so sensor readings may be up to 2 seconds old when using our library. Connect the left - most pin to 3 - 5V power, the second pin to your data input pin, and the right - most pin to ground. Note that it's not Dallas One Wire compatible, and each sensor in a multi - sensor setup needs its own data pin. We offer an Adafruit Learning System guide with schematics, Arduino & CircuitPython code, and datasheets. Compared to the DHT11, the DHT22 is more precise, accurate, and works across a wider temperature and humidity range, though it's larger and costlier. The kit comes with a 4.7K - 10K resistor for pulling up the data pin to VCC.
Using the DHT22 sensor is straightforward. First, connect the left - most pin to a power source between 3V and 5V. Then, link the second pin to your data input pin. Make sure to connect the right - most pin to the ground. Remember, this sensor isn't compatible with the Dallas One Wire system. If you plan to use multiple sensors, each one should have its own dedicated data pin. When getting data from the sensor, keep in mind that you can only get new readings every 2 seconds. So, your readings might be a bit old. As for maintenance, there's not much to do. Just keep it clean and away from extreme conditions. The kit includes a 4.7K - 10K resistor that you should use to connect the data pin to the power supply. If you need more help, check out our Adafruit Learning System guide with useful schematics and code.
