remote control dimmer

The S566B IC manufactured by Siemens forms the basis of an excellent light dimmer. The circuit is operated by a touch switch and is able to regulate the light intensity smoothly without steps. This circuit, therefore, does not make use of a potentiometer or any other moving parts, which are subject to wear and tear. A basic design for this IC was originally published in the Summer Circuits 78 issue. The IC controls a triac which will only conduct for the period of time determined by the IC. This time period will dictate the amount of power used by the light bulb and thus the light"s intensity. The conduction angle may be regulated between 30° and 150° of each half cycle of the mains waveform. As mentioned, the dimmer is operated by means of a touch switch. If this is touched briefly (between 60 and 400 ms) the light will burn at the previous level preset. Touching the switch for the same amount of time again will switch the light off. When the TAP is touched for longer than 0.4 ...