I’m in the process of testing the QS165 V2 with FocKING. Using only 6 mosfets for this (as a starting point). I haven’t done any thorough testing with 12 mosfets. Maybe other’s have (sat-be).
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I recall Shaman saying once that putting FET’s in parallel to handle more current could cause problems. But I don’t recall why.
I just asked ChatGPT to tell me what potential issues could arise. Here’s the interesting part (I think)…
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Keep gate traces short and use individual gate resistors for each FET to prevent oscillations and ringing.
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High-speed switching can lead to oscillations, so snubbers or gate resistors might be needed.
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That’s right. Sometimes it works, and sometimes it doesn’t, which is why I state that it has not been thoroughly tested yet by me (but maybe by others - like Mr. sat-be). I can tell that the MP2 board (using same mosfets and gate resistor values as foc-king) successfully implement mosfets in parallel.
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Check… Foc-king has both of these precautions implemented - but again, not thoroughly tested by me 
I have tried with 12 mosfets, but never intentionally tried to kill it with a destructive test.
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I am waiting for your results
I checked the JLCPCB, and they dont have STM32, only the APM32F405RGT6. Can i use this is?
Not sure that you should wait for my results, because I can never do a general test on this that will work fore everybody.
Now, the King has individual gate resistors and snubbers, but there are more precautions than that. With stuff in parallel, you don’t know which path the current will take. The more current that goes through a specific mosfet, the hotter it gets. Resistance decreases with more heat, which means that more current passes through, more heat, blah blah… A dead spiral. So most importantly with mosfets in parallel:
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Good heat sinking… Big chunk of Aluminium (which is expensive these days, btw - in the Gulf of Mar-a-Lago)
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Mosfets with properties as similar as possible. They should come from the same batch.
Just jump into it… Heat sinking is not a part of the King, so I can’t test. V2.0 is a pre-release, so you could also wait two weeks for the final release.
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i preordered some and got them 2 days ago
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Works quite well in my Onewheel but to really torture it hard I would have to install it in my efoil, what I do not intend to do at the moment.
In the onewheel normal motor current is only 40A max 60 and some short spikes to 120A.
It stays quite cool, I added a 3mm aluminium plate as a heat sink to the FETs. The alu plate is screwed to the front box from cast aluminium, 0.5mm heat transfer pad between.
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Okey, i am waiting for v2
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I preordered 5pcs.
Somebody tried to connect 2 controllers with canbus?
I want to use it in dual motor escooter.
this should work over canbus .
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@jens_overby So i was experimenting with some pin headers. I think if we could reorder some PILL output there should be no need for an expensionboard cause you could just connect the esp32-c3 directly on the PILL.
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You’re right. There is something with +5V and +3.3V that needs to switch position. That’s where I left it also… But what about CAN - you still need wires to external CAN-extension, or ?
Thanks Daniel for showing some pictures. Did you use “mica” sheets for electrical insulation, or?
In original vescs, mosfets are “glued” to the aluminium with some stuff. Anyone knows what it’s called and where it can be purchased?
yes at the moment you would need an external can wire
Thermal Interface Material.
Google thermal pad and you’ll find plenty of alternatives