How to diagnose mosfet with lab-supply ?

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  • Acnologia
    Badcaps Veteran
    • Dec 2016
    • 422
    • Poland

    #1

    How to diagnose mosfet with lab-supply ?

    Hello to everyone ,

    So far most of the repairs that i've been doing was novice, i would say. With a lot of help from you gents.

    Now ,i got in my hands a lab-supply. So , i have a laptop in my hands that doesn't turn on , remains dead , but at the same time there is no short circuit in the main line (as i think off).

    I know that i should put 1v-2v to ground (black wire) and red wire to close the circuit to a specific place after the DC-IN port.
    Now the question is, where do you place it most of the time , i mean in which specific place after the power port ? Is any place , the same to make the capacitor or the part to heat up and understand where is the short ? (I have thermo camera from phone) so i can easily find it i believe.

    But i'm not sure where do you place the 'red' wire of the lab-supply ,so it's better to ask rather than blow myself up in my face
  • mon2
    Badcaps Legend
    • Dec 2019
    • 14570
    • Canada

    #2
    https://youtu.be/wp1dPG9_N1w?si=a27Hg6sm8RHZBvo5

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