bedside lamp timer schematics


Posted on Feb 6, 2014

Q1 and Q2 form an ALL-ON ALL-OFF circuit that in the off state draws no significant current. P1 starts the circuit, the relay is turned on and the two ICs are powered. The lamp is powered by the relay switch, and IC2 is reset with a positive voltage at pin 12. IC2 starts oscillating at a frequency set by R4 and C4. With the values shown, pin 3 goe


bedside lamp timer schematics
Click here to download the full size of the above Circuit.

s high after around 30 minutes, turning off the circuit via C3. During the c6 minutes preceding turn-off. The LED does a blinking action by connections of IC1 to pins 1, 2 & 15 of IC2. Blinking frequency is provided by IC2 oscillator at pin 9. The two gates of IC1 are wired in parallel to source more current. If required, a piezo sounder can be connected to pins 1 & 14 of IC1. Obviously, timings can be varied changing C4 and/or R4 values.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    Contrast meter
    Warble Alarm Circuit
    Logic Probe With Sound
    uhf tv pre amplifier
    magnet
    interfacing servo motor with 8051 using keil c
    Telephone Circuits
    CD47 (Rodan) Nixie Tube Clock
    Current Limiting for Redundant Power Systems
    Homemade wireless remote control circuit diagram



    Top