Getting to Know the TP223 Capacitive Touch Sensor

What happened

Mechanical and prone to failure, switches can seem quaint these days. Plus, everyone is used to having touch screens on their phones and other devices.

[Tarantula3] has details on using the TP223 instead of ordinary switches . These inexpensive modules work through plastic, glass, or wood, opening up many interesting possibilities for building a front panel.

Of course, the thicker the surface above the module, the less sensitive the switch is, but that’s not always a bad thing. Thicker panels, reducing the size of the touch pad, or adding an external capacitor can reduce the sensor’s range.