Voltage Regulator

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  • stephkre
    Member
    • Jul 2009
    • 26

    #1

    Voltage Regulator

    I have a voltage regulator on a circuit, part number L7805CV, and I get around 32 volts on the input and 14.88 volts on the output. What I want to know is that enough volts for the circuit to operate on when it says it needs 15V? I know there is some logic that is supplied by this voltage.

    The reason this is concerning me is because there is a bypass cap on the line (the one that goes from the circuit to ground) that was bad. I dont think the low voltage caused it; however, what would be effected by the cap blowing. The device I am working on is a CLSC-12S subwoofer it turns on but has no sound coming out. I checked the transistors on the circuit they seem to be fine.
  • Radio Fox
    Badcaps Veteran
    • Jan 2010
    • 281
    • UK

    #2
    Re: Voltage Regulator

    I asume you mean an L7815CV.

    14.88v is well within the tolerance of the regulator (14.25V to 15.75V under load conditions).
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    Comment

    • larrymoencurly
      Badcaps Veteran
      • Oct 2004
      • 960
      • USA

      #3
      Re: Voltage Regulator

      Don't 78xx type voltage regulators need only 2-3V more coming in than going out?

      OTOH some of them have a power-saving feature that for some reason makes them put out almost the full input voltage unless the output load is at least 25mA (2.5mA? I'm not sure). I think ST brand was or is like that.

      Comment

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