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  1. #1
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    How to test MOSFET using digital multi meter?

    How to test N or P channel MOSFET using digital Multi Meter, how to determine its Gate Drain & source pins via DMM

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    FvM
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    mosfet testing

    It's generally not necessary to check the pin mapping, cause no manufacturer uses a mapping different from industry standard (as far as I know). Polarity can be determined with a multimeter/diode tester from the drain source reverse diode.
    If threshold voltage is below diode tester maximum (e. g. 2 V), also identification of a three-terminal blackbox-FET would be possible, but usually it's not necessary.


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    •   Alt12th May 2008, 15:50

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    test mosfet

    test the pn junctions.


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    how to test a mosfet

    first connect dmm red lead to drain and black on the source.(meter should be on diode test mode)
    in first case drain to source will be open.
    then connect meter red probe to gate and black to source and again connect the red probe to drain and black with source.now it will show the short circuit.after this short the gate and sorce with some wire now again drain to source will show open circuit.
    it means that mosfet is good


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    how to check mosfet

    MOSFET TESTING
    Another type of semiconductor you should become familiar with is the metal oxide semiconductor field-effect transistor (MOSFET), as shown in figures 2-19 and 2-20. You must be extremely careful when working with MOSFETs because of their high degree of sensitivity to static voltages. As previously mentioned in this chapter, the soldering iron should be grounded. A metal plate should be placed on the workbench and grounded to the ship’s hull through a 250-kilohm to 1-megohm resistor. You should also wear a bracelet with an attached ground strap and ground yourself to the ship’s hull through a 250-kilohm to 1-megohm resistor. You should not allow a MOSFET to come into contact with your clothing, plastics, or cellophane-type materials. A vacuum plunger (solder sucker) must not be used because of the high electrostatic charges it can generate. Solder removal by wicking is recommended. It is also good practice to wrap MOSFETs in metal foil when they are out of a circuit. To ensure MOSFET safety under test, use a portable volt-ohm-milliammeter (vom) to make MOSFET resistance measurements. A vtvm must never be used in testing MOSFETs. You must be aware that while you are testing a MOSFET, you are grounded to the ship’s hull or station’s ground. Use of a vtvm would cause a definite safety hazard because of the 115-volt, 60-hertz power input. When the resistance measurements are complete and the MOSFET is properly stored, unground both the plate on the workbench and yourself.


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    •   Alt19th May 2008, 05:09

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    mosfet tester

    where are the figures?


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    testing mosfets

    The precautions said by randell_xtian are necessary without doubt for unprotected small-signal MOSFET, particularly small geometry RF devices. Power MOSFET are more or less protected and have high gate capacitances that need a lot of charge accumulated to create dangerous voltages, I would expect an ESD susceptibility not higher than for small-signal bipolar devices. Usual ESD protective equipment is recommended in a professional enviroment anyway.



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    mosfet test

    pls. check the attachment:


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    Re: How to test MOSFET using digital multi meter?




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    Re: How to test MOSFET using digital multi meter?

    Quote Originally Posted by weak.element View Post
    Thanks for your update as a reply by the last post belong to a 3 year old date, and the OP may have got the reply quite long back. Anyways your post may be helpfull for future querries related to the same.
    Cheers



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    Re: How to test MOSFET using digital multi meter?

    Quote Originally Posted by pranam77 View Post
    Thanks for your update as a reply by the last post belong to a 3 year old date, and the OP may have got the reply quite long back. Anyways your post may be helpfull for future querries related to the same.
    Cheers
    Yes, it is...



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