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. So why not use touch sensors on your next project? [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. In particular, you may want to reduce sensitivity anyway. Thicker panels, reducing the size of the touch pad, or adding an external capacitor can reduce the sensor’s range.You may be worried about eating up batteries with a bunch of electronic switches. But according to [Tarantula3], the modules consume less than 2 microamps at rest. You can configure the modules with our favorite scripting language: solder. There are two jumpers, initially unsoldered, and this results in four possible states. By default, the output goes high when someone is touching the sensor and stays high until they release.However, you can solder jumper A to invert the output. Jumper B causes the switch output to toggle on each press. Of course, you can also do both jumpers, which toggles but has the opposite default state. If you get false triggers, consider adding a small capacitor to filter the power supply to the module.These would be great “drop ins” for 3D printing to add switches to your designs. You might even be able to use these as power switches with a little work.