Mosfet goes from reading to OL

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  • Icitte
    Senior Member
    • Aug 2011
    • 61
    #1

    Mosfet goes from reading to OL

    HI guys

    I have a Toshiba Mosfet K3569

    When I test it, the reading between D and S (after turning on) get from a voltage and getting higher until OL in an seconde or so. Is that a normal situation or a bad MOSFET?

    All bad mosfet video I saw on youtube only show shortened reading between D and S .

    Thanks

    And sorry if my english is bad!
    Last edited by Icitte; 09-25-2018, 02:14 PM.
    Tags: None
    • redwire
      Badcaps Legend
      • Dec 2010
      • 3900
      • Canada
      #2
      Re: Mosfet goes from reading to OL

      It is normal, testing a mosfet from D-S, the gate is sensitive to static charge.
      If you first "charged" the gate to turn it on, then it will slowly lose charge with the gate not connected.

      You must short G-S to ensure mosfet is off. Then look for a short or leakage across D-S.

      To look for a short or leakage across G-S or G-D, there is nothing to worry about.
      Last edited by redwire; 09-25-2018, 05:15 PM.

        Comment

        • Brucetafer
          Senior Member
          • Jun 2018
          • 133
          • USA
          #3
          Re: Mosfet goes from reading to OL

          I just changed 2 brand new mosfets that tested perfectly fine, but wouldn't close the gate with a load... so just replaced them with budm recommendations..

            Comment

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