Yes, I just advise you not to buy chips on Aliexpress, because this is the information I know. Happy shopping!
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I have some doubts about the traces of the current acquisition. The traces form a right angle. Will it not form a strong signal reflection? Is it better to trace the traces at 45°?
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I had never even heard of that (perhaps because I’m not a real EE). So I looked it up. This guy is dispelling myths, but claims that this one has a miniscule bit of truth to it…
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It depends on the signal. As a rule of thumb I’d say yes. Use 45 degree angles. In this case it dsn’t matter that much 
But it hurts my eyes a little bit looking at it, I must admit. (I have sensitive eyes)
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In fact, it is easy to understand, maybe the electronic movement is not intuitive, but I will compare the current to the flow of water. When the water flow meets a right angle (or there is an obstacle in front of it), there will be waves, and the faster the water flow, the bigger the wave. Perhaps it does not have much impact on low-speed signals, but we should try to avoid problems that can be avoided.
Yes, I guess I’m sensitive too. This is because I had a bad time with the current sense trace when I was playing with Odrive, so I will remember the lesson.
Finally some news. It has been a summer full of work to be done on a lot of other things.
I’ve ordered the first 4-layer-pcb’s today.
- And I will fix the missing 45 deg angle at the shunts in future versions.
- Checked in the new design on GitHub - nordstream3/FOC
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It’s my first shot at a 4-layer pcb, so there’s likely some “tuning” I need to do. You’re welcome to review - I can take it. I am a newbie who needs to learn all the tricks.
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Interesting. I don’t recall signing off on “other things”! 
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It might be interesting to separate the power electronics onto a separate single sided pcb, so that it could be made from alu for better cooling.
I might give it a go when I have some time and the design is finalized.
Unless you’re paying a fortune for heavy copper I think the “standard” Al boards are only 1/2 or 1oz copper…pretty thin for all that current. Check with your board house to be sure.
2-layer, or even 4 or 6 layers, has some real advantages and cooling isn’t that much worse with a good set of thermal vias and Al heat spreader plate.
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Using multiple PCBs can introduce a lot of problems when heavy vibrations are considered. The specific way they are connected becomes very important. I wouldn’t want a power board connected to a logic board with just header pins. Especially not under extreme and prolonged vibration.
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I saw the trend in some spintend vescs and they had very good thermal performance, I run one in my onewheel build.
I agree that the connection between the two board would have to be properly engineered.
One additional question, there are smd variants of the mosfets that were mentioned previously, us there a reason why vescs are still sticking with through hole mosfets? I saw couple lfocs where they failed on the mosfet legs, one from the person who sold me an xr motor :D.
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It could be cost or availability but there’s also thermal fatigue. Components with “legs” are much less susceptible to cracking and failing over time due to the difference in how much they expand when hot compared to the circuit board.
The circuit board expands a lot more and that puts a lot of strain on the cases of surface mounted components that don’t have the ability to flex a little like components with “legs” can.
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I managed to blow up both the assembled boards I received from china. I was just about to bring it alive, when I accidentally shorted the gate driver input to 12V.
Now, when trying to order another batch, the STM32F405RGT6 is suddenly out of stock at jlcpcb. Bad Bad Bad news…! I don’t want to solder that part myself. Until now only succeeded 1 out of 3 times on that part. Will have to wait, I’m afraid.
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Oh no! Sorry to hear that. I find that the easiest way to solder stm32 is to get 2 corner pins on then flux the heck out of it and drag the iron along one side at a time. I usually check for shorts at the end with a mm.
mail me your boards and spare MCUs and I’ll resolder them for free and post em back to you.
Think we’re in the same town?.. or am I misstaken
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Hi @jens_overby
First time forum user so please bear with me if I am asking something that already got answered.
Interesting project here. Are the PCB layout on Kicad only? I have used Easyeda to build some of my PCBs before. Can we use the schematic as is in easyeda or you won’t recommend that?
The reason is ask is I will want to combine your schematic with some of my other logic board schematics to build a single PCB.
Thanks
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Well, I think it can be used in Easyeda, but I don’t know much about Easyeda, except that I have previously imported gerber files from Kicad in Easyeda. I have attached gerber and bom, if you can use that for anything in Easyeda.
gerber.zip (451.0 KB)
bom.csv (4.7 KB)
Same city… Hmm, I’m on the west coast of Kattegat and I think you’re on the east coast. But thanks for trying to help me out. However, I have ordered a new batch of 5 with the mcu, and it should arrive in 1 or 2 days.