The MPR121 supports I2C only, making it compatible with most microcontrollers. You can select one of four addresses via the ADDR pin, allowing up to 48 touch pads on a single I2C bus. It simplifies capacitive sensing, handling all filtering and allowing sensitivity adjustments.

This sensor is on a breakout board with a 3V regulator and I2C level shifting, so it’s safe with 3V or 5V microcontrollers like Arduino. An LED on the IRQ line blinks when touch is detected, aiding in visual debugging. The board includes headers for breadboard use, and for touch pads, copper foil or pyralux is recommended.

Start quickly with our Arduino library, tutorial, and example code. Now featuring SparkFun qwiic-compatible STEMMA QT connectors for plug-and-play I2C without soldering. (QT cable sold separately.)

Features:

1. I2C Support: Compatible with most microcontrollers, using a single I2C bus.
2. Address Selection: 4 selectable addresses via ADDR pin, enabling up to 48 touch pads on one I2C line.
3. Automatic Filtering: Handles all filtering for capacitive sensing, with configurable sensitivity.
4. Breakout Board: Includes a 3V regulator and I2C level shifting for compatibility with 3V or 5V microcontrollers.
5. Touch Indicator LED: Blinks on touch detection for easier debugging.
6. Breadboard-Friendly: Comes with 0.1″ header for easy prototyping.
7. STEMMA QT Connectors: SparkFun qwiic-compatible connectors for solder-free I2C connection.
8. Compatibility: Works with Arduino and CircuitPython, with dedicated library and tutorial.
9. Accessory Support: Compatible with various STEMMA QT accessories (QT cable sold separately).

Package Includes:

1 x Adafruit 12-Key Capacitive Touch Sensor Breakout – MPR121