Description

HTU21D Humidity Sensor

The HTU21D Humidity Sensor is a low-cost, easy to use, highly accurate, digital humidity sensor.This new humidity and temperature sensor is about to set new standards in terms of size and intelligence and also it is ideal for environmental sensing and data logging, perfect for a weather station or humidor control system.

Features

• Supply Voltage:2.1 to 3.6 V
• Uses the I2C interface
• Typical humidity accuracy of ±2%
• Typical temperature accuracy of ±0.3C
• Operates from 0 to 100% humidity but this sensor is not recommended for harsh environments where it could come in contact with water (such as rain).

Hardware Connections

The SHT21 Humidity Sensor should be connected to Uno as follows:

• VCC to 3.3V of Arduino uno
• GND to GND of Arduino uno
• SDA to A4 of Arduino uno
• SCL to A5 of Arduino uno

#include 
#include "HTU21D.h"
//Create an instance of the object
HTU21D myHumidity;
void setup()
{
  Serial.begin(9600);
  Serial.println("HTU21D Example!");
  myHumidity.begin();
} 
void loop()
{
  float humd = myHumidity.readHumidity();
  float temp = myHumidity.readTemperature();
  Serial.print("Time:");
  Serial.print(millis());
  Serial.print(" Temperature:");
  Serial.print(temp, 1);
  Serial.print("C");
  Serial.print(" Humidity:");
  Serial.print(humd, 1);
  Serial.print("%");   
  Serial.println();
  delay(1000);
}

Guide