RC delay

Discussion in 'General Electronics Chat' started by banzai, Nov 2, 2014.

  1. banzai

    Thread Starter Member

    Jan 3, 2014
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    Hi

    This is a simple RC delay, only issue here is i can't see how the cap will discharge after i has been charged. Using a resistor across the RC would work, but it would be a slow solution. Is there a way to make the capacitor discharge faster then using the resistor ?.

    [​IMG]

    Thanks in advance guys
     
  2. ScottWang

    Moderator

    Aug 23, 2012
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    Using a diode.
     
  3. Papabravo

    Expert

    Feb 24, 2006
    10,137
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    Sure. Use a transistor switch
     
  4. banzai

    Thread Starter Member

    Jan 3, 2014
    71
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    :s where would it be placed ???

    The plan is to make it discharge when the power is removed
     
  5. ScottWang

    Moderator

    Aug 23, 2012
    4,853
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    Using a diode as 1N4148 in parallel with R and the negative connecting to V, the positive connecting to C.

    When the power is removed then the C current will from C flows through R to V, that is the C discharge, the C current will also flows through Vc to the Load.
     
    Last edited: Nov 2, 2014
  6. banzai

    Thread Starter Member

    Jan 3, 2014
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    But that would be a short circuit
     
    Last edited: Nov 2, 2014
  7. crutschow

    Expert

    Mar 14, 2008
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    It's rather hard to make a circuit without having it be a circuit. :confused:
     
  8. banzai

    Thread Starter Member

    Jan 3, 2014
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    0
    Sorry. I meant short circuit.
     
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