DHT22 humidity Capacitive Digital Temperature and Humidity Module is a temperature and humidity composite sensor providing a calibrated digital signal output. DHT22 module offers highly precise, more accurate, and works in a bigger range of temperature/humidity. But quite larger and more expensive compared to DHT11. Using dedicated digital module acquisition technology and temperature, humidity sensor modules ensures the products with high reliability and excellent long-term stability. The module consists of a capacitive humidity sensor and a thermistor sensor connected to a high-performance 8-bit microcontroller.
It measures the surrounding air and outputs a digital signal on the data pin (no analogue input pins are needed). It’s quite simple to use but requires careful timing to grab data. The new data is obtained from it once every 2 seconds. So when using our library, sensor readings can be up to 2 seconds old. DHT22 module consists of an inbuilt filtering capacitor and pull-up resistor. But for the sensor, you have to use them externally if required. The breakout board used in the module makes installation quite simple.
DHT22 module offers easier connections by simply connecting the red wire to 3-5V power, the yellow wire to your data input pin, and the black wire to the ground. Although it uses a single wire to send data it is not as One Wire compatible. In case if you want multiple sensors, each one must have its own data pin. The DHT22 module offers better humidity measuring range, from 0 to 100% with 2-5% accuracy. DHT22 Temperature and Humidity Sensor Module features Small size & low consumption & long transmission distance (100m) makes it ideal for all kinds of harsh application occasions. These are designed as Single-row packaged with four pins, making the connection very convenient.