I soldered a board that can drive two brushless dc-motors (common for modelmaking). After solving some problems both motors were running properly.
After adaption of the mechanical part, one mosfet wasn't working any more. Removing the mosfet made clear that the TMC389 driver stage for this mosfet wasn't working any more.
I ordered a new TMC389 and replaced the old one. After providing power to the mosfets, one path was fully destroyed (not that one with the previous problem). I don't know the reason but it could be a soldering problem.
I removed the two related mofets but now the communication via SPI is not working any more, but I'm not sure if this problem still occured before the failure with the mosfets.
The signal on SDO is about 1 Vdc overlaid with small part of signal on SDI and SCK (few millivolts). Do you think I destroyed the TMC389?
I don't know how to prove proper operation of the TMC389 in the removed state.
Before ordering a new TMC389, I want to clarify the reasons for the problem (I unfortunatelly got no financial support from the university and the tmc389 is not cheap part for a student)
thank you in advance.