Why are there two inputs mosfets?

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  • mikay786
    Badcaps Veteran
    • Aug 2014
    • 765
    • UK

    #1

    Why are there two inputs mosfets?

    Just trying to fix this old Alienware m14x laptop.

    found a shorted capacitor and a shorted mosfet on the input mosfet pair.

    im i newish to this and was wondering why you almost always have a pair of identical mosfets on in the input? They both do the same thing so what the point?

    also on a side note i am eager to test laptop since no short now, is there a way to bypass the 2nd mosfet for a temporary solution until replacement arrives?

  • mikay786
    Badcaps Veteran
    • Aug 2014
    • 765
    • UK

    #2

    Comment

    • mon2
      Badcaps Legend
      • Dec 2019
      • 14508
      • Canada

      #3
      https://electronics.stackexchange.co...lways-in-pairs

      Comment

      • mikay786
        Badcaps Veteran
        • Aug 2014
        • 765
        • UK

        #4
        Cheers

        Comment

        • rumpumpel1
          Senior Member
          • Jul 2019
          • 159
          • germany

          #5
          In addition to the main purpose of a bidirectional switch, the first MOSFET also serves as an inrush current limiter.

          Comment

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