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Unread 23-09-2006, 18:46
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Al Skierkiewicz Al Skierkiewicz is offline
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Re: victor 885 parts

Quote:
Originally Posted by Cirrussport
The resistors that go to the fets are on the supply then? I figured they were on each gate to make sure that the gates were getting the right voltage. Well victors seem very well engineered. looking at the board (this is just theory, correct me if im wrong) you could technically solder on 3 more fets to the bottom of the board for each string for a total of 24 on board fets aslong as you put a separate resistor for each gate.(i know its not very practical but in theory it would work right?)

Thanks again
The resistors would normally be in the drain lead. It has been a while since I opened one up, but I seem to remember the gates and sources tied in parallel while the resistors are in series with the drain and then out to the load for the high side FETs and in the source for the low side.
Your idea about added FETs is correct, theoretically adding as many FETs as are needed to make up the current. Some factors might get in the way of success such as turn on time and source to drain "ON" resistance but for the low switching frequency of the Victor the turn on time should not be a problem. Of course the circuit traces are sized for the expected current so you might have to redesign the way power and output leads are treated.

All in all, they are pretty cool little devices for $129.
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Al
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