Aliexpress is infamous for relabeled mosfets and fake ics, sadly. Though lcsc should be safe. Mouser should be 99.999% real. But it is what it is, sometimes it’s hard to tell.
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Designing a 2-layer board forces you to think about what you are doing. But I have come to the conclusion that it just makes no sense for a high amp motor driver. I can probably make it work, but what I gain by spending 3 dollars on two more layers, will always be a better solution.
I’m converting everything to a 4-layer board, and this will delay things, and then again, I don’t think it will delay anything in the end.
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I agree. Fortunately, the decision of fets doesn’t need to be taken right now.
CRST030N10N is available at LCSC for around $1/pcs, and it satisfies the specs. It’s produced by CRMICRO… I would prefer if it was Texas Instruments or Infinion, or something more non chinese. Suggestions are welcome
Required specs:
VDS >= 100V
RDS(on) <= 3mΩ
ID (continous) > 150A
Now with 4 layers, the fets might not need to be of type TO-220
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HOWEVER, CRST030N10N is used in the MESC MP2 board, which I trust very much, so I think I will go for this specific mosfet, available cheap at LCSC.
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Any reason not to use gh 1.25mm connectors? They are cheap of jlcpcb and smd so they will solder it for you and are smaller then standard just connectors
More fragile wires and deviating from the standard PH2.00mm that all VESCs use maybe? Im not sure you can use larger than 30awg on GH 1.25mm but you can use 24awg on PH2.00mm and in the case of motor sensor wires, I would want to use the largest feasible gauge for robustness.
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It would be cool to create tutorial videos on youtube - “how to create “FOC KING”” and attach an archive with all the necessary files. So that everyone can appreciate your wonderful creation. I have great respect for you from your work on this project. 
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A lot of the ubox vesc use them, and it has a clip built in to no need to hot glue the connectors in
Hi.
I have to apologize for not being very active at the moment. The thing is that I currently have a 10 t sailboat standing on land. I need to fix the bottom of this boat - it’s worse than expected. Life is full of surprised.
I expect it to be 2 weeks more of work. Sorry guys
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Osmosis?
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Yes, one layer should be only the ground plane, and should have no (zero, none, zip, seriously!) traces on it.
Otherwise you get eddy ground currents and all kinds of weirdness and there is no way to model what is going on.
We paid a consultant a lot of money to learn this.
And what are we waiting for now?
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This behaviour is exlusive to alot of things tho. I’ve made plenty of PCBs with a few cutouts on one or more ground planes without issues.
But yes I agree, its good practice to let it be
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Agreed.
100% layer coverage for a ground plane (on a nearby layer in the stack up) is always best but you can break it up with traces if you understand where the return currents are trying to flow through the ground layer.
Low frequencies/rise time stuff doesn’t matter much as the return current is so smeared out but the ultra-fast rise time and high freq return currents want to flow directly beneath the associated components/traces. Extending the path the return currents need to follow will increase the board’s emissions and possibly affect EMI/RFI susceptibility.
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Yes, for simple circuits it doesn’t matter, but for anything with high power components, high speed or audio I think it makes a big difference.
Also I always use via’s to tie broken up GND planes together. So keep all the copper in the unused islands on the top plane, but tie each island into the bottom layer’s GND plane. I also tie each corner of the PCB together top GND to bottom GND. Via’s are free, I use a lot of them.
and of course physical spacing of power traces away from signal traces.
This is also common practice.
Most of the stuff I’ve designed has a bluetooth SoC with a PCB antenna I tuned myself.
Is 2.4Ghz fast enough for you? 
I think dealing with harmonics count as much as power applications tbh.
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I do not recommend you to buy chips on AliExpress or Taobao, because this is also a recognized untrustworthy path in China. Or you need to ask the seller, let him guarantee you a brand new chip. We generally make purchases at LCSC.
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So I thought I’d found some great deals on FS4K IC’s on Alibaba. I even managed to order some. But to make a long story short, I have never in my life succeeded in purchasing anything from Alibaba - and I still haven’t. I really thought I was ahead because this is the first time I managed to actually place an order. But it’s pretty clear that allowing me to place an order was an error on their part.
I have had luck with everything I’ve ordered from AliExpress so far, but I’m giving up on Alibaba for another 5 to 10 years before giving them another try. And I don’t think I’ve ever bought chips from AliExpress, but other stuff has been OK.