Hello, I just wanted to solicit anyone who may have some more experience dealing with mosfets. My current situation is this: I've designed and build a pcb that uses the FQP30N06L to turn on and off some 100w cob leds. I typically run these leds at 50w, and they are at roughly 50v. There is a teensy that controls the pwm to the fets (so 3.3v). The FQP30N06L is rated for 79w (with cooling), 60v, 30a, and works with 3.3v boards (also, my pwm frequency is 244 hz). I've got a fan over them, but no heatsinks due to space constraints. The FQP30N06L typically get pretty warm, my thermocouple measures 90-100 F which is in spec (175C max junction temp). I've ordered them from sparkfun in the past and always received the Fairchild branded ones.
Recently, I ordered more FQP30N06L from amazon since the shipping from sparkfun would be more expensive, and found they were no longer manufactured by Fairchild semiconductors because they have been bought by ON semiconductor. The ones from amazon immediately shorted on and burnt up. I thought maybe I had received some chinese ripoff product, so i ordered from mouser... same problem! I should note, however, that the ON FQP30N06L seem to work fine at 12v to turn some relays on and off (so basically, they only fail at higher powers).
I also ordered some IPP50N10S3L-16 along side the FQP30N06L and they seem to work fine! This is bonkers.
Has anyone else had experience with these mosfets or getting counterfeits that don't meet the data specifications? They all look identical, except the old ones have the Fairchild logo instead of ON.
I called mouser and they will be replacing the failed FQP30N06L with IPP084N06L3 G which is very similar but has a much lower RDs on of 8 mOhms instead of 35 mOhms, but otherwise similar specifications.
Here are pictures of the new FQP30N06L that don't work, and the old FQP30N06L by fairchild that have been running on my board for a while. Pardon the quality, my phone doesn't pick up the writing that well.
here are the relevant data sheets
FQP30N06L (2001 data sheet)
FQP30N06L (2013 data sheet)