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Clamping circuits.mechansim

  1. Oct 9, 2011 #1
    clamping circuits.......mechansim

    See i have a problem regarding clamping circuits:
    1.what do we mean when we say that "capacitor allows ac to pass through it but stops dc"
    2.please see the attachement

    Attached Files:

  2. jcsd
  3. Oct 10, 2011 #2


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    Staff: Mentor

    Re: clamping circuits.......mechansim

    The impedance of inductors and capacitors is frequency-dependent. For capacitors, the impedance is inversely proportional to frequency. So the impedance of a capacitor is infinite at DC, and zero at very high frequencies. The configuration in your diagram is a high pass filter, with low frequencies and DC current not making it through the capacitor, and high frequency currents passing through the capacitor to the resistor.

    See the current-voltage relation information for capacitors here, for example:


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