kinarfi
Well-Known Member
Still killing IRF3205 FETS left and right and I don't know what's wrong
I have a pile of 19 dead IRF3205 on my table and they all but 2 have the same markings and I'm sure I have smashed and/or trashed about the same amount, I think I got them off eBay and I'm starting to wonder if they are truly International Rectifier or a knock off. When I killed the last one, I had circuit hooked up to a 180 watt, 14v gear motor, one end of the gear motor has the sensor in it, something similar to a Wheatstone Bridge, and the other end is the power output, I held the output shaft with a pair of pliers and turned the input shaft with another pair of pliers while watching the current read out of my power supply, I was getting about 15 amps out when one of the FETs failed shorted, I can only load the gear motor up a little compared to when it's in actual use.
These are 110 amp FETs, 15 amps to a set of paralleled FETs shouldn't be killing them!!!
I've brought this up before and tried multiple ways to drive the FETs IR2110, Totems, this time the gate driver was the out from a 555, and they still keep dying and not doing the job.
I gave up on an H Bridge and went to relays to switch the polarity to the motor to save on FETs, while slower, it's plenty fast for what I need and I can concentrate on the FET driver.
Any ideas??? Should I mail the dead FETs to IR so they can see if they're theirs or knock offs.


Jeff
ps the markings
IRF3205
I R P138D
B9P0

These are 110 amp FETs, 15 amps to a set of paralleled FETs shouldn't be killing them!!!
I've brought this up before and tried multiple ways to drive the FETs IR2110, Totems, this time the gate driver was the out from a 555, and they still keep dying and not doing the job.
I gave up on an H Bridge and went to relays to switch the polarity to the motor to save on FETs, while slower, it's plenty fast for what I need and I can concentrate on the FET driver.
Any ideas??? Should I mail the dead FETs to IR so they can see if they're theirs or knock offs.


Jeff
ps the markings
IRF3205
I R P138D
B9P0
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