how to test a Voltage Regulators

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  • mcross
    Badcaps Veteran
    • Sep 2011
    • 201
    • USA

    #1

    how to test a Voltage Regulators

    Hi guys, how do i test a (278RA05) 2A Output Low Dropout Voltage Regulator

    Thanks for any info
  • PlainBill
    Badcaps Legend
    • Feb 2009
    • 7034
    • USA

    #2
    Re: how to test a Voltage Regulators

    Originally posted by mcross
    Hi guys, how do i test a (278RA05) 2A Output Low Dropout Voltage Regulator

    Thanks for any info
    I just measure the output voltage. If it isn't correct, I check the input voltage. For more exhaustive tests, look up the datasheet - they often include test circuits.

    PlainBill
    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

    Comment

    • Scenic
      o.O
      • Sep 2007
      • 2642
      • Germany

      #3
      Re: how to test a Voltage Regulators

      looks to be a 7805 variant with an extra pin for adjusting the voltage or disabling the output.

      1st pin: input
      2nd pin: output
      3rd pin: GND
      4th pin: either voltage adjustment or output disabling

      if the 4th pin isn't connected to anything, you should see 5V DC on pin 2
      Attached Files

      Comment

      • mcross
        Badcaps Veteran
        • Sep 2011
        • 201
        • USA

        #4
        Re: how to test a Voltage Regulators

        thanks, will check it now

        Comment

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