The Si7021 is a low-cost, easy to use, highly accurate, digital temperature and humidity sensor. All you need is two lines for I2C communication, and you’ll have relative humidity readings and accurate temperature readings as well! This sensor is ideal for environmental sensing and data logging, perfect for a weather station or humidor control system.
The Si7021 also comes equipped with a hydrophobic PTFE filter covering the inlet on the sensor. This filter blocks contaminants but allows water vapor to pass through, keeping your sensor safe from water damage while still proving accurate sensor readings.
- 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 10kΩ resistors to limit 5V signals
- Only one Si7021 sensor can reside on the I2C bus at a time