DHT22 temperature and humidity sensor

The DHT22 temperature and humidity sensor is a low-cost high precision humidity and temperature sensor with a single wire digital interface, meaning many of these sensors can be strung (daisy chained) together from one digital pin.

The sensor is pre-calibrated and doesn't require extra components so you can get right to measuring relative humidity and temperature.

DHT22 temperature and humidity sensor Features:
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

Sketch example

/* DHT11/ DHT22 Sensor Temperature and Humidity Tutorial  * Program made by Dejan Nedelkovski,  * www.HowToMechatronics.com   */ /*  * You can find the DHT Library from Arduino official website  * http://playground.arduino.cc/Main/DHTLib  */   #include <dht.h> #define dataPin 8 // Defines pin number to which the sensor is connected dht DHT; // Creats a DHT object void setup() {  Serial.begin(9600); } void loop() {  int readData = DHT.read22(dataPin); // Reads the data from the sensor  float t = DHT.temperature; // Gets the values of the temperature  float h = DHT.humidity; // Gets the values of the humidity    // Printing the results on the serial monitor  Serial.print("Temperature = ");  Serial.print(t);  Serial.print(" *C ");  Serial.print(" Humidity = ");  Serial.print(h);  Serial.println(" % ");    delay(2000); // Delays 2 secods, as the DHT22 sampling rate is 0.5Hz }