CMOS dimmer
Siemens’ Type SLB0586A IC enables the simple construction of a dimmer with touch control. Used in conjunction with a Type TIC206D triac, it allows the dimming of light bulbs of 10-400 without any problem. A 100 pH, 5 A inductor is needed to suppress the switching noise.
Synchronizing pulses are derived from the mains voltage via R1 1, C4, and D4, and these are applied to pin 4 of the IC.
The supply voltage is obtained by means of R2, C2, D1. D2 and C3, and lies about 5.3 V “below the mains voltage. The touch key used to operate the 1C is connected to pin 5 via two 4.7 NIQ resistors, R5 and R6, to guarantee the safety of the user. Since dimmers are often built into an existing circuit, there is frequently a need for operation from two different locations. Consequently, the diagram shows a 1 additional push-button switch that may be situated well away from the touch key.
The diagram also shows three jump leads. 5 which are intended for selecting one of three modes in which the IC can work. When jump lead B is used, the light is always switched on at the last used level, whereas when A or C is used, the light comes on at minimum brightness. When B or C are used, the dimming direction reverses every time dimming is used; this is not the case when jump lead A is used. When the touch key is touched briefly, that is, for 50-400 ms, the light is switched on or off; if it is touched for a longer period, the dimming cycle is started.