AT42QT101X Capacitive Touch Breakout Hookup Guide

Contributors: Elias The Sparkiest, Shawn Hymel
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If you need to add user input without using a button, then a capacitive touch interface might be the answer. The AT42QT1010 and AT42QT1011 Capacitive Touch Breakout boards offer a single capacitive touch button with easy-to-use digital I/O pins. For convenience I'll refer to both versions of this board as "AT42QT101X" but I'll refer to each individual version when talking about their differences.

SparkFun Capacitive Touch Breakout - AT42QT1010

SparkFun Capacitive Touch Breakout - AT42QT1010

SparkFun Capacitive Touch Breakout - AT42QT1011

SparkFun Capacitive Touch Breakout - AT42QT1011


The AT42QT101X is a dedicated, single-button capacitive sense chip. The chip handles monitoring a conductive area for touch. As long as a touch (e.g. from a finger) is detected, the AT42QT101X keeps the output line high. Otherwise, the line is kept low. You just need to provide a power source (1.8V - 5V) and ground for the AT42QT101X to work. SparkFun's breakout board contains an on-board electrode capable of detecting touches. Additionally, a PAD pin is available if you would like to create your own external electrode.

Covered In This Tutorial

This tutorial will show you how to connect the AT42QT101X Breakout Board to an Arduino along with some example code to read the board's output. Additionally, alternative ways to use the board will be shown, such as mounting it to an acrylic panel and creating your own capacitive sensing pad.

Required Materials

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