Here’s some cool quick notes on touch sensors QT113/118 for those of you trying to invent touch enabled systems.
I need a touch sensor for a couple of projects, and the Qprox QT113 seems to be the way to go, particularly for interfacing with an Atmel processor. It’s easy to work with, and hooks-up with only a bare minimum of extra stuff. All you need is a resistor and capacitor and a bit of wire or trace to compose the sensor.
Tom Igoe documents most of the deta