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Different voltage drop on two identical mosfets

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u666sa:
Mosfets are FTW20N50A, I have them off the board. Both check out okay using testing technique in diode mode. Except, one shows voltage drop 0.2501 and the other one 0.4858

Is that okay or no okay?

WaveyDipole:
Did you short the source and drain before applying the DMM?

u666sa:
Of course! Did it for both, measured several times, each time shorting.  :-//

CaptDon:
How do you test a MOSFET with drain shorted to source??? I short the gate to source and look for an open between D and S or the body diode if measuring in the opposite direction. I have also done gate shorted to drain to see that the MOSFET is conducting. If I did D shorted to S I would hope to see an open circuit in both directions measuring to the gate and to not blow up the gate by stressing the barrier from excessive gate voltage.

u666sa:
I short gate to drain with tweezers.
Black probe source, red drain. Reads open.
Black probe source, red gate and then back to drain. It reads voltage drop.

Same precedure on both mosfets. Except each one reads different voltage drop.

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