Courtesy Lighting with 7555

  
This circuit is intended to let the user turn off a lamp by means of a switch placed far from bed, allowing him enough time to lie down before the lamp really switches off. 15 seconds delayed switch-off A good idea for bedroom lamps. Obviously, users will be able to find different applications for this circuit in order to suit their needs.

Due to the low current drawing, the circuit can be supplied from 230Vac mains without a transformer. Supply voltage is reduced to 10Vdc by means of C1 reactance, a two diode rectifier cell D1 & D2 and Zener diode D3. IC1 is a CMos 555 timer wired as a



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