Simple 12V Lamp Dimmer

This simple lamp dimmer is ideal for small halogen capsule lamps or ordinary 12V incandescent bulbs.

The circuit operates as a variable pulse width modulator using the ubiquitous 555 timer chip. The 1N4001 diode (any of the 1N4000 series can be used) acts to prevent swithching spikes from the lamp damaging the Power Mosfet.

The circuit can easily be built on some perforated board of stripboard so a PCB is not really required. A wide variety of power mosfets can be used and an excellent device is the HUF75337P3 which is available in the UK from Maplins, Order Code: UE47B.

For further information on electronics and components see the Electronics section.