DHT22 is a popular temperature and humidity based digital sensor. This is the upgraded version of the DHT11  sensor. The sensor uses a capacitive humidity sensor and a thermistor based temperature sensor to measure the ambient humidity and temperature.
The humidity sensing ranges from 0% to 100% with ±1% accuracy and the temperature sensing ranges from -40 degrees to the 80 degrees Celcius with ±0.5°C accuracy. The sampling time of this sensor is 2 seconds almost.
This Temperature and Humidity Sensor uses digital pins to communicate with the microcontroller unit and does not have any kind of analog pins. The module also has the inbuilt pull-up resistor and additional filter capacitor to support the DHT22 sensor. Thus the module is available in ready to go mode and can be directly connected with the microcontroller unit without using any kind of additional components.
DHT22 Sensor Specifications
Operating Voltage: 3.5V to 5.5V
Digital I/O
5 Hz sampling rate (Once every 2 Seconds)
Measuring current: 0.3mA
Low power consumption
Temperature range: -40 to 80 degree C
Humidity range: 0% to 100%
Accuracy: ±0.5°C and ±1%
Dimension: 5x 4 x 2 cm