Nice ! So its working. How many amps are you pulling on those 2 vescs? Are you running 6 oder 12 FETs per Controller?
Many thanks. 
I’ve found an interesting buck ic the u3504d it runs up to 150v, dirt cheap and can even do dual outputs 5v and 12v. It might be possible to simplify the power supply design here and reduce part count.
I’ve written an email to the company since the datasheet is missing the values for current sense resistor, but otherwise it should be pretty capable.
Hi Jens,
Have any luck finding the files for the MESC → FreeDrive port?
Really keen to give this a try. Did you have to change ADC assignments etc, as the schematic looks quite different to say the reference MP2 … by the way, great work on the prop drive …
I‘m still struggling with the power pcb. If I connect a 12V power source to the 12V pin, the 5V circuit works as expected. But connecting 16V to the VIN pin doesn‘t turn on the tx4130 buck converter, even if the two pads on the back of the pcb are shorted.
I also checked the resistors and other components, I didn‘t find any error.
Any ideas?
Ok, looks like I found the problem by accident. There’s no continuity between VIN and VDD of the TX4130. When shorting the two legs, the buck converter turns on and I get 12V as well as 5V.
I don’t really understand, what the intended way of switching the buck converter on and off is, but at least in my case shorting the two pads on the back of the pcb doesn’t seem to be enough.
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What if you turn up the voltage on Vin to e.g. 24V. Does that make it work?
No, the input voltage didn’t matter, but I finally was able to make the other 4 PCBs work. I guess the TX4130 was somehow damaged.
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I am having the same issue, I think pin 9 is the pad underneath, the IC, and soldering by hand is difficult. I will try forcing some solder through the vias from underneath the board.
Yep, flux + heat +solder on the vias under the TX4130, made the connection. All works
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Loos like I have to run only 6 FET’s as 12 won’t fit due to conflict with the powersupply 3 pin inter-board connector. See picture.
Should be doable if you put the converter pins flush to the board and solder just from top
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12 mosfets per board… I have some trouble connecting a potentiometer throttle. I think it’s the machine pin headers not making a very good connection. Anyone else than who’s had problems with these headers?
I have just got mine working (6 fets), for 12 fets I will replace the machine header with pins of the same diameter. With the pins of the socket, there is only just enough length to make contact, but you have to make sure no raised blobs of solder …
For the potentiometer, I thing I remember 22 awg solid wire pushed into the machined socket? I havn’t got to that point yet. Anyone know where to get that cable from?
Anyone know where I can get some insulator sheet like this:
https://nz.element14.com/bergquist/sp1500st-0-008-00-0404/sil-pad-1500st-008-4-x-4-sheet/dp/1893433
… but cheaper … I intend pressure mounting my board to the back of an aluminium box (don’t want to use the screw holes)
Did you have a Look at AliExpress?
I ordered this one a few days ago, but there are also bigger ones available.
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Better take one with high thermal conductivity:
I just found this on AliExpress: US $4.96 | 20 W/mK Thermal conductivity Thermal pad 100x100mm High quality CPU Heatsink Cooling Conductive Silicone Pad thermal insulation
https://a.aliexpress.com/_EIO5m6O
The thinner the better, I use 0.5mm with good results.
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Dont scare me, i need to use the adc chanels for escooter .
Thanks but, Isn’t it the lower the better? I found one at 0.8W/mK.
