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Paralleling FET's
Steve
To put FET's in parallel, you have to find out each one's turn on
information exactly. Then you have to put equalizing resistors in the
gate so that they all turn on at the _same_ time and the _same_ amount.
If you don't, you get to watch the casing fly right off one of the little
buggers when they hog the power. I am not sure what the value range of
resistor you will be needing. To find the individual turn on info, you
will need your multimeter, a wrap around circuit and a paper and pencil
to record stuff. Basically, your wrap around circuit has a load resistor
on the source or drain. You have a few resistors and a switch so you can
select the one in the gate. You set your multimeter up to measure
current through the FET. You put a controlled voltage that _must_ remain
constant during your testing. You measure the current flowing through
your FET with a medium-sized resistor. Then you write down this value.
Put the next FET in. Change the gate resistor until the current through
your 2nd FET is as close to the first as possible. Then take the next
FET and so on. You might want to test a few before you try equalizing to
make sure you get a current value that is in the median of the other's.
EE's: If I made a mistake please correct me.
Bryan
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