DHT22 (or AM2302) is a low cost high precision humidity and temperature sensor with a single wire digital interface.It utilizes exclusive digital signal collecting technique and humidity sensing technology and can ouptut calibrated digital signal. Small size & low consumption & long transmission distance (20 meters) enable AM2303 to be suited in all kinds of harsh applications.
Power voltage shoud be between 3.3V and 6V DC. When power is supplied to sensor don’t send any instruction to it withing one second to pass unstable status. One 100nF capacitor can be added between VDD and GND for wave filtering.
- 3.3 – 6 V Input
- 1-1.5 mA measuring current
- 40-50 uA standby current
- Humidity from 0 – 100 % RH
- -40 – 80 degrees C temperature range
- +- 2 % RH accuracy
- +- 0.5 degrees C
- 20 m max wire length
How to use :
You can use the DHT22 humidity/temperature sensor and the Arduino UNO board to read data and print it out to the serial monitor or to display it on an LCD. The videos below shows how to realize this application.
PART 1: Read air Temperature and Humidity from DHT22 sensor using Arduino board
PART 2: Display air Temperature and Humidity from DHT22 sensor using LCD display
In order to realize this project you will need the following components :
DHT11 / DHT22 Sensors
1 kohm pull-up Resistor
I2C Liquid Crystal Display