About DHT11/DHT22 Temperature and Humidity Sensor:
DHT11/DHT22 are used for measuring the temperature and humidity of the surrounding. It consists of a capacitive type humidity sensor for measuring humidity and a thermistor for measuring temperature. The values from both the sensors are fed to a chip present inside on the circuit board which converts analog data to digital data. The data can be further used for other applications.
Pinout of DHT11/DHT22
Features of DHT11
- Low cost
- Voltage: 3-5 volts
- Current: 2.5mA
- Humidity: 20-80%
- Temperature: 0-50 degree Celsius
Features of DHT22
- Low cost but expensive than DHT11
- Voltage: 3-5 volts
- Current: 2.5mA
- Humidity: 0-100%
- Temperature: -40-80 degree Celsius
Components Needed
- DHT11 or DHT22
- Arduino UNO
- Jumper Wires
Pin Connection of DHT11/DHT22 with Arduino
- Pin VCC: 5v
- Pin GND: GND
- Pin OUT: Pin2
Circuit Diagram of DHT11/DHT22 with Arduino
Arduino code of DHT11/DHT22 with Arduino
#include"DHT.h"
#define DHTPIN 2
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);
void setup(){
Serial.begin(9600);
dht.begin();
}
void loop(){
int hum = dht.readHumidity();
int temp = dht.readTemperature();
Serial.print("Humidity: ");
Serial.println(hum);
Serial.print("Temperature: ");
Serial.print(temp);
Serial.println(" *C");
}
}