GY-21 Si7021 SHT21 I2C High Precision Humidity Temperature Sensor
The Si7021 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 build a weather stations or humidor control system.
The sensor from Silicon labs has ± 3% relative humidity measurements with a range of 0–80% RH, and ±0.4 °C temperature accuracy at a range of -10 to +85 °C. Great for all of your environmental sensing projects. There are only four pins that need to be hooked up in order to start using this sensor in a project. One for VIN, one for GND, and two data lines for I2C communication.
The sensor breakout board has a 3.3V regulator and level shifting so you can use it safely with 3.3V or 5V power & logic. There's a PTFE filter to keep the sensor clean, that's the white flat thing on top. Also comes with some header pins.
Resources:
Datasheet
Arduino Tutorial
Raspberry Tutorial
Si7021 Arduino Library
Package includes:
1x GY-21 Si7021 Temperature & Humidity sensor
GY-21 Si7021 SHT21 I2C High Precision Humidity Temperature Sensor - Arduino Pi
New: A brand-new, unused, unopened and undamaged item in original retail packaging (where packaging is applicable). If the item comes direct from a manufacturer, it may be delivered in non-retail packaging, such as a plain or unprinted box or plastic bag. See the seller's listing for full detail