swicthing circuit

Discussion in 'The Projects Forum' started by ben, Aug 20, 2006.

  1. ben

    Thread Starter New Member

    Aug 20, 2006

    I want to make a circuit that when a pressure/push switch has been activated for 4 seconds it then activated an infra red led. The infra red led must then stay on all the time until it is reset by a reset button.

     The infra red led will need a battery to power it up 24 hours once it has bee activated. Could you tell me what kind of battery I could use (the smaller the better)?
     The led I hope to use is kingbright KM-4457F3C

    Part No. KM-4457F3C
    Material GaAs
    λP(nm) 940
    Lens Type water clear
    Po(mW/sr) @20mA *50mA Min. 0.8
    Po(mW/sr) @20mA *50mA Typ. 5
    Viewing Angle 2θ1/2 150º

    The switch just needs to be a small push switch or pressure switch like a micro switch.
    The time period that the chip counts to when the switch is in activation doesn’t have to be that accurate (around 4 seconds) .

    I believe I will need a counter e.g (555 chip) and another chip. Would you be able to draw the circuit full as I only know the basics. And also write down the resistor/parts sizes I will need to make this circuit.
    I would be extremely greatful if you could find the time to help me out.