For those of you who want to control dimming of your house lights “digitally” using a single seven-segment display to show its brightness, you might want to take a look at these free circuit schematics on making a digital light dimmer. It’s not in English but the code could still be very helpful. (Blog post in English)
The light level can be adjusted with two push-buttons “Up” and “Down”. Controller in this application is PIC16F84 that drives BUZ11 mosfet. Dimmer is tested with a light bulb 12V/4W and mosftet didn’t get even warm (which was expected since the datasheet says: 50V/30A). There is a small 5V voltage regulator on board LM78M05 (0,5 A) for the PIC microcontroller. Light level can be adjusted to 10 steps (0-9) and upon startup it is automatically adjusted to level 5. Current light level is displayed on 7-segment LED display with common anode. PCB was designed in Proteus and firmware is written in PBP.