Adafruit 12 x Capacitive Touch Shield for Arduino - MPR121

by Adafruit

This touch-able add on shield for Arduinos will inspire your next interactive project with 12 capacitive touch sensors.

Capacitive touch sensing works by detecting when a person (or animal) has touched one of the sensor electrodes. Capacitive touch sensing used for stuff like touch-reactive tablets and phones, as well as control panels for appliances, which is where you may have used it before. This shield allows you to create electronics that can react to human touch, with up to 12 individual sensors.

The shield has 12 'figure 8' holes in it that can be gripped onto with alligator clip cables. Attach one side of the clip to the shield and the other side to something electrically conductive (like metal) or full of water (like vegetables or fruit!) Then start up our handy Arduino library to detect when the object is touched. That's pretty much it, very easy! For advanced users, you can also solder to a pad to make a slimmer & more permanent connection. Works great with any Arduino as it only uses the I2C pins (SCL & SDA).

It uses the same chip as the MPR121 12-Key Capacitive Touch Sensor Breakout so you can duplicate the library and code! Adafruit have examples for reading touches. Using an Arduino Leonardo and a little bit of creativity you can use it to turn touches into keyboard KeyUp/KeyDown presses (so you can make a veggie-keyboard) or pair it with a Music Maker shield to create an audio player that will play a sound per sensor (fruit drums!)

Each order comes with a Capacitive Touch Shield and a stick of 36-pin headers. You'll need to do some light through-hole soldering to attach the headers onto the shield circuit board, but its easy to do with basic soldering tools like a soldering iron and rosin core electronics solder. You'll also likely want to pick up a pack of alligator clips!

Please note! This kit does not come with Arduino, alligator clips, or delicious fruit! However, we do have all of those in the store. Well, all except fruit...

Technical Details

Revision History:

  • As of December 5, 2022 – Adafruit have updated this PCB to have the I2C pullups go to a configurable solder jumper and default to the Vref pin from modern Arduino boards. This will make it work a lot nicer with 3V Arduino-shaped boards. They've also updated the silk with Adafruit Pinguin to make a lovely and legible silkscreen.