Adafruit Si7021 Temperature & Humidity Sensor Breakout Board

It's summer and you're sweating and your hair's all frizzy and all you really want to know is why the weatherman said this morning that today's relative humidity would max out at a perfectly reasonable 42% when it feels more like 77%.

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 · 3-5V input · 3.3V output, up to 100 mA

Confirm the data interface matches your host board.

Module pins: Vin, 3v3, GND, SCL, SDA. Schematik maps them to your board in the app.

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