SparkFun Capacitive Touch Breakout - AT42QT1011

If you need to add user input without using a button, then a capacitive touch interface might be the answer. The AT42QT1011 SparkFun Capacitive Touch Breakout offers a single, momentary capacitive touch button with easy-to-use digital I/O pins.

The AT42QT1011 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 AT42QT1011 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 AT42QT1011 to work. Additionally, a PAD pin is available if you would like to create your own external electrode.

Unlike its sibling, the AT42QT1011 does not have an internal time-out, meaning that if you hold your finger to the breakout’s pad for any length of time, it will stay on. The difference between the AT42QT1010 and the AT42QT1011 is small but may be a game changer depending on your project’s uses.

GET STARTED WITH THE AT42QT101X CAPACITIVE TOUCH GUIDE

If you would like to add some proximity ability (so that the device will respond without actually touching the capacitive pad, just getting close to it), our customer Voon-Li had some success by replacing the 10nF capacitor just under the PAD connection (C2 in the schematic), with a 100nF capacitor, and also using an external electrode, which is discussed in in the guide. Thanks for the feedback Voon-Li!