Here is a simple capacitive touch switch circuit for electronics hobbyists. Even though the circuit uses smd components, construction of the touch sensor switch is not very hard because the whole ...

This PLL-based circuit implements a touch-switch circuit using the PC board or small metal pads as sensors; it is radiometric and thus insensitive to changes in temperature and supply voltage.

You can’t have a touch sensitive switch without a way to detect the presence of a finger! A touch sensor, especially a capacitive touch sensor, has some surprisingly sophisticated electronics to ...