The HTU21D is a low-cost, easy to use, highly accurate, digital humidity and temperature sensor. This sensor is ideal for environmental sensing and data logging and perfect for weather stations or humidor control systems. All you need is two lines for I2C communication and you’ll have relative humidity readings and very accurate temperature readings.
It is a very good replacement for digital humidity sensors such as the SHT15, SHT21, SHT25, HIH-4030, HIH6130 and capacitive humidity sensors such as the HH10D.
There are only four pins that need to be hooked up in order to start using this sensor in a project. One for VCC, one for GND, and two data lines for I2C communication. This breakout board has built-in 4.7k pull-up resistors for I2C communications. If you’re hooking up multiple I2C devices on the same bus, you may want to disable these resistors.
Overview:
- Digital humidity and temperature sensor
- Environmental sensing & data logging
- I2C communication
- Operating voltage: 1.5V - 3.6
- Humidity measurement range: 0 - 100%RH
- Temperature measurement range : -40 °C - 105 °C
Features:
- Uses the I2C interface
- Typical humidity accuracy of ±2%
- Typical temperature accuracy of ±0.3C
- Operates from 0 to 100% humidity but this sensor isn’t recommended for harsh environments where it could come in contact with water (such as rain).
- 3.3V sensor - use inline logic level converters or 10k resistors to limit 5V signals
- Only one HTU21D sensor can reside on the I2C bus at a time
Specifications:
- Supply voltage: 1.5V - 3.6
- Humidity measurement range: 0 - 100%RH
- Temperature measurement range : -40 °C - 105 °C
- Maximum power consumption : 2.7uW
- Communication method : I2C
- Humidity accuracy range ( 10%RH to 95%RH ): HTU21D±2%RH
- Humidity hysteresis: ±1% RH
- Measurement time: 50ms
- Annual drift: -0.5%RH/year
- Response time: 5 s
- Dimension: 1.5 × 1.6cm (approx)
- Weight: 5 g
Application:
- Automotive: defogging, HVAC
- Home Appliance
- Medical
- Printers
- Humidifier
Compatible Product:
Pinouts:
- Vcc - 3.3 V
- Gnd - Gnd
- SCL - Serial Clock
- SDA - Serial Data
Note: Full drops of water can damage the sensor. We recommend wrapping the board in Teflon/irrigation tape for extreme conditions where water droplets may find their way into the sensor.
Package Includes:
- 1 x HTU21D Temperature & Humidity Sensor Module I2C Interface
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