Test power lines with diode mode

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  • corrize
    Badcaps Veteran
    • Apr 2021
    • 272
    • France
    #1

    Test power lines with diode mode

    Hello, I have a noob question about troubleshooting (for laptop in my case but, it's could be general).

    I saw someone on video testing power lines witn diode mode. He saw 0.1v on 5v line and said « it's too low », and compared with 3.3v line and find 0.3v (seems OK for him). How did he know it's too low or not pls ?
    Tags: None
    • redwire
      Badcaps Legend
      • Dec 2010
      • 3902
      • Canada
      #2
      Re: Test power lines with diode mode

      Semiconductors have a (IC substrate diode) threshold voltage of about 0.3V-0.7V and using a multimeter on diode-test it will first charge up capacitors and then settle on a voltage reading for that line.
      Anything less than 0.3V is considered a short.

        Comment

        • corrize
          Badcaps Veteran
          • Apr 2021
          • 272
          • France
          #3
          Re: Test power lines with diode mode

          Thanks, it's clear.

            Comment

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