I'm hoping I might find some answers or help to this issue here on this forum. I hope this is the right place to ask. The MOSFET in question is labeled mcac80n06. I've tried to source the original chip but as with most transistors it's extremely hard to find them. I've tried contacting the original manufacturer but no response.
My question for finding a replacement MOSFET for an application like an esk8 is how critical are things like vgs, vds, vdss, current gain, on resistance on so forth. I got se recommendations from the folks at digikey but it seemed like the parameters were to out of spec for my liking.
The other thing is will replacing one MOSFET out of the set of 6 used for the 3 phases on one motor cause an issue with how smooth the motor will function.
And maybe easier than all this since Lacroix is based over the pond is there any one, any of you guys can recommend to potentially do the repair if this process is just honestly too advanced for me.
Thoughts opinions? I'm in no rush since I picked up a focbox unity to get me by in the mean time.
if mosfet's package type hsof or psof it is easy to find, example FDBL86363-F085 .
pqfn ?
I believe it's a pqfn type
Ben
The most important thing is the package. If the replacement is not identical, you'll likely have thermal problems. If you do not have experience desoldering/soldering SMT packages, that may be your biggest challenge. YouTube can help.
The nice thing about MOSFETs is that, unlike BJTs, they will share current equally assuming the original circuit design and layout is correct. (EDIT: True, but this only applies to paralleling.)
You want the replacement's parameters to be as least as good as the original's. A higher drain-source voltage rating is fine. A lower on-state resistance is fine. The gate-drive characteristics are best matched by looking at curves. You could do much worse than taking Digi-Key's recommendation.
With 6 MOSFETs, you have a pair for each of the three phases.
Assuming it works at all, motor smoothness will not be affected.
One other thought. Remove the blown MOSFET and try to run the controller at less than half rated current. It should work if there are no other problems.I don't know why I wrote that, it's wrong for your situation. There are not 2 MOSFETs in parallel for each phase. There's one high-side switch, and one low-side switch for each phase winding. Glad I caught that error reasonably quickly.