A PIC controls a triac connected across the supply by monitoring power line zero-crossing. The PIC controls dimming by delaying the time the triac fires, which trims the peaks off of the AC waveform.

Lucid Lighting has supplies a truly customisable range of triac-controlled, leading-edge dimmers called Hyrax. They are able to control: Incandescent or tungsten lamp-loads of up to 5000 watts per ...