TTP223 Capacitive Touch Lamp

A copper pad behind plastic, one IC, and a MOSFET — touch anywhere on the surface to toggle a string of LEDs.

Difficulty: Breadboard. Estimated build time: about 30 minutes. Estimated parts cost: about US$4.60. 5-part bill of materials with live supplier pricing. A touch-activated lamp that uses no buttons or switches — just a pad of copper foil hidden behind a plastic enclosure.