HTU21D Temperature and Humidity Sensor I2C

The HUT21D is an inexpensive and accurate digital humidity and temperature sensor. Thanks to the I2C interface, you can easily read out the humidity and temperature. This sensor is perfect for a weather station or other applications where you want to measure the humidity.

Important info: Activating the I2C Pull-Up Resistors:
There are two 4.7k Ohm resistors on the breakout board that pull up the SDA and SCL lines. If you want to run multiple sensors on the I2C, only one breakout board should have the resistors. On the HUT21D breakout board, the resistors are not connected to VCC by default. To activate them, you must connect the three solder points on the top of the board with solder.

Links HTU21D Arduino Library:

• https://github.com/enjoyneering/HTU21D
  
• https://github.com/sparkfun/SparkFun_HTU21D_Breakout_Arduino_Library
  
• https://github.com/adafruit/Adafruit_HTU21DF_Library
  

Downloads HTU21D:

• HTU21D Datasheet

Technical Details:

• Operating voltage: 1.5-3.6V
  
• Interface: I2C
  
• Humidity measurement range 0 to 100% RH
  
• Temperature measurement range: -40°C to 125°C
  
• Humidity accuracy: +/- 2 % RH
  
• Temperature accuracy at 25°C: +/- 0.3°C
  
• Dimensions: 15 x 15 x 2.7mm
  
• Weight: 1.5g
  

Package includes:

• 1x HTU21D Temperature and Humidity Sensor I2C
  
• 1x Pin header 4x1p