Adafruit 12-Key Capacitive Touch Sensor Breakout - MPR121

The Adafruit MPR121 Capacitive Touch Sensor Breakout provides 12 channels of capacitive touch sensing over I2C. The MPR121 handles all the capacitive filtering internally and can be configured for varying sensitivity levels, making it far easier to use than raw analog capacitive sensing.

With four selectable I2C addresses via the ADDR pin, you can connect up to four breakouts on a single bus for a total of 48 touch pads. The board includes a 3V regulator and I2C level shifting for safe use with both 3.3V and 5V microcontrollers, plus an IRQ LED that blinks when touches are detected for easy visual debugging.

Key Features

• 12 Touch Channels – Independent capacitive touch inputs with built-in filtering
• I2C Interface – 4 selectable addresses for up to 48 pads on one bus
• 3/5V Compatible – Onboard 3V regulator and I2C level shifting
• IRQ LED – Visual indicator blinks on touch detection
• Configurable Sensitivity – Adjustable filtering and threshold settings
• Compact Breakout – Pre-soldered MPR121 chip ready for breadboarding

Also Available

• MPR121 Capacitive Touch Shield for Arduino – Shield format with alligator clip pads

Ideal For

• Interactive touch interfaces and control panels
• Musical instruments and touch-based triggers
• Proximity sensing and gesture detection
• Replacing mechanical buttons with touch pads

Package Contents

• 1× Adafruit MPR121 12-key capacitive touch sensor breakout (assembled)
• 1× 0.1" header strip

Specifications

• Sensor Chip – MPR121
• Touch Channels – 12
• Interface – I2C (4 selectable addresses)
• Logic Level – 3.3V or 5V