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  1. #1
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    opamp delay

    Hi
    I want a op- amp(LM324) based one second time delay startup circuit

    with regards
    satya

    •   Alt8th January 2006, 02:37

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  2. #2
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    delay opamp startup

    Use 1/4 of 324 in "comparator" configuration - see picture below ..
    Time dalay of a RC circuit can be calculated as follows:
    t[s] = R(in Ω) * C(in Farads)
    Try to use R1 = 1MΩ and C1 = 2.2µF, and with Ra and Rb set the level at ≈80% of Vs (supply) .. this should give you ≈1s delay ..

    Regards,
    IanP



    •   Alt8th January 2006, 05:51

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  3. #3
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    op amp delay

    Battery input voltage is 8.0v to 12v

    i want Ra,Rb value

    with regards [/img]



    •   Alt8th January 2006, 09:13

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  4. #4
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    analog delay opamp

    For Ra=10kΩ (100kΩ) and Rb=39kΩ(390kΩ) the 80% condidtion will be true for Vs=8V, but it won't be true for Vs=12V ..
    If you would like to make this circuit independent of the Vs voltage, wire 1kΩ resistor in series between Vs and (Ra+Rb<->R1+C1), and an 8.2V zener diode in parallel with (Ra+Rb<->R1+C1) ..

    Regards,
    IanP



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    op amp time delay

    madarchod lodo ghanta hila lo
    behan ke lodo koi circuit nahi chal raha hai apni maa chuda lo



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