Adafruit MCP2221A Breakout - General Purpose USB to GPIO ADC I2C
USB to GPIO/ADC/I2C bridge board using the MCP2221A chip, allowing a host computer to directly control I2C sensors, GPIO, and analog inputs without a separate microcontroller. Includes STEMMA QT/Qwiic connector. Works on Windows, macOS, and Linux with HID drivers.
Pinout
- STEMMA QT SDAType · Signal
- STEMMA QT SCLType · Signal
- STEMMA QT 3VType · Power
- STEMMA QT GNDType · Ground
| Pin | Type |
|---|---|
| STEMMA QT SDA | Signal |
| STEMMA QT SCL | Signal |
| STEMMA QT 3V | Power |
| STEMMA QT GND | Ground |
Pin details
4 connections- STEMMA QT SDASignal
- STEMMA QT SCLSignal
- STEMMA QT 3VPower
- STEMMA QT GNDGround
Start wiring
USB · 3.3 V
Confirm the data interface matches your host board.
Module pins: STEMMA QT 3V, STEMMA QT GND, STEMMA QT SDA, STEMMA QT SCL. Schematik maps them to your board in the app.
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