Adafruit Si7021 Temperature & Humidity Sensor Breakout Board
I2C temperature and humidity sensor breakout based on the Si7021. Works at 3.3 V or 5 V with onboard level shifting and pull-ups, suitable for weather stations and HVAC monitoring.
Pinout
- VinVin
Board power input. Adafruit states the onboard regulator accepts 3 to 5 VDC and safely converts it down for the Si7021 breakout.
Type · powerVoltage · 3-5V input - 3v33v3
3.3V output from the onboard voltage regulator. Adafruit states up to 100 mA can be drawn from this output.
Type · powerVoltage · 3.3V output, up to 100 mA - GNDGND
Common ground for power and logic.
Type · ground - SCLSCL
I2C clock pin. Connects to the microcontroller I2C clock line. Adafruit states the fixed I2C address is 0x40.
Type · clockVoltage · Logic level follows host/power wiring - SDASDA
Start wiring
I2C · SPI · Single data line · 3.3 – 5 V · Breakout
Confirm the data interface matches your host board.
Module pins: Vin, 3v3, GND, SCL, SDA. Schematik maps them to your board in the app.
Temp & humidity
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