These are connected by the PCB anyway so it doesn’t matter.
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Did some more checks for solder bridges on the DRV chips, i did not find any. The stuff on the pics is just some rosin residue from the flux.
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dang it, drv ships are kinda sold out on a couple of sites
Too much tip for too long can also kill, flat slanted tip with plenty good flux, wipe on, wipe off Daniel-San. The ground of course is not an issue with this design which is a huge plus.
Pure IPA for cleanup and the nice Japanese tissues or Q-Tips. That looked like a bridge but on closer inspection it’s maybe some remaining flux as you say.
You can run 12v for testing which is less likely to bring the 
. Spending time correcting possible problem areas with a lens is time well spent.
Get nice flux/solder/paste, it makes life easier, this kind of specialist stuff
https://www.doc-solder.ie/store/soldering-flux/RMA-Paste-Flux-10cc
https://www.doc-solder.ie/store/Soldering/Solder-Wire/Lead-Free-Solder-Wire
Some long tipped tweesers are really handy for positioning components well
I would defer to @Agressivstreetlamp @shaman @JohnnyMeduse but the above worked for me as a psuedo-noob for smd assembly, in particular the tricky DRV
Not linking lead products as you need to have ventilation solutions and there are quality lead free options from my experience
Did they all blow on R48? That is very weird unless there is a component orientation problem, bad pcbs, or as you say bad quality component
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+1 leadfree
Also, getting this working without hot air would be wildly impressive. Personally, It looks like the ARM is not aligned correctly.
Also, realize that the R at the end of DRV8301DCAR is simply a packaging thing. the Big 3 (Digikey, Mouser, Arrow) all list both. Basically, they buy the R (Bulk) and cut you off a slice.
https://www.arrow.com/en/products/drv8301dcar/texas-instruments
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I read somewhere that it is good practice to power a new soldered board with a current limiting power supply, so you dont burn chips. Do you put a little solder on the ground pad before putting on the DRV and soldering it from the back site vias?
@shaman Is the FOCer also running the Ackmaniac firmware?
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I’ve only ever used the VESC firmware. The Cheap FOCer is 4.12hw based so it should work with any Ackmaniac firmware for 4.12 hardware.
I read this post about Ackmaniac’s software and then the exchange between individuals and Trampa. It seems like others have experienced issues with the motor detection of the newer VESC tool just as I did. I think I might give Ackmaniac’s firmware and software a try.
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Thank you, yes all 4 of them blew the R48. I first suspected putting one of the diodes the wrong way but i checked and it was fine. Also running the board on 5V made the leds lit up so i thought it was ok to run 19V
@Agressivstreetlamp how do you think it is not aligned? programming went fine…
@Colip61 Yes, i would absolutely have used that, but i dont have an current limiting power supply. Its on top of my shopping list now.
No, i just put some flux on the backside. I thought about that but i was worried it will not sit flat on the pcb.
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It’s hard to tell but I just looks like it’s too far to the right.
But I could be wrong.
If we had 4 ics at work that blew the same component under normal conditions we’d call it a job well done and hand it back to the designers and tell them to fix their shit. Cough Cough @shaman cough Cough
Let me take a look on a real monitor
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Can you confirm C34 direction and function for me? if you check across it it should be an open. (very high ohms)
and check Pins 33 and 34 for shorts.
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Can we get some more pictures? This area looks like one big solder ball.
Also where are the shunts R53 and R54
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Except that they have been made by others and work already proving the design?
Not an E.E so perhaps other variables come into play like component quality, pcb quality. Whether the design has inherit fragility’s over a standard 4.12 I doubt it.
18v would not be a factor that’s for sure.
The solder job is not up to professional standards no offense @doomy but I guess why you’re asking. Maybe send in one of the pcbs for inspection by @shaman to see if there is anything to learn , avoid & share by all.
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@magharees Yes I was just joking. But 4 boards with the same failure does not sound like a botched solder job. More like a misplacrd or bad component. Component quality definitely can matter but if as long as all the components match the same ratings you should be ok. Actually Alan, that’s brilliant!
@doomy did you order the exact BOM or did you have to get any alternatives?
I’d say your solder work is pretty damn good for iron work. AnY 0603 that stays with an iron is an achievement. I apologise if it sounds like I’m bashing your work
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Thanks guys, got a hot air gun from a friend and removed one of the DRVs, now im waiting for some new ones, they should be here next week.
It seems that using the vias for connecting the GND plate does not work that well.
Where did you get that schematic ? This is where R48 is on the board:
Some more pics of the boards. There is some leftover rosin residue in that area on the first board.
I know that my soldering dos not look that nice. Its the first time i soldered SMD components other than a few resistors here and there. Maybe if i go over it with the hot air gun it will look better, but as long as it is doing its job im completely ok with it.
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Doh, I was using the original vesc 4.12 schematic haha duhhh.
Try that and let’s see how it goes.
And 18v is not stressing anything. I can’t double check the BOM on my cellphone against placed components in the pics.
Well I could, but that would make me single again 
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I mean I feel like your priorities are mixed up, but I understand.
The BOM question was also for Doomy…
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I had to replace some of the components that were out of stock from shaman’s original BOM.
LCSC BOM for 5 pieces:
Do you remember which 5?
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I dont remember but it was only resistors and maybe 1 capacitor…