Other Parts Discussed in Thread: DRV8350
We have designed a speed controller for BLDC motors based on DRV8350 and we have been experiencing pretty much the same problem described in [1].
We started working with the hardware version of the DRV8350 and after having six units destroyed during the testing we changed to the SPI version which is more versatile and let us check the cause of the faults. With the SPI version we adjusted the lowest value for the gate currents (IDRIVE) that avoids ringing (300mA/600mA), but even though it took more testing time to get into troubles than with the H version, we are still finding the same problem as described in the [1] post: while the motor is spinning the driver suddenly fails with GDF fault condition in Fault Status Register 1, and at least one of the VGS_XY fields set on Fault Status Register 2. When we measure the Zout of the gate drive indicated in Fault Status Register 2 we always find that the Zout of that specific gate drive (as measured from the GLX pin of the DRV8350S to ground) is too low (sometimes zero) instead of around 140k.
VM is 12V, and the VDrain of the MOSFETs is 67V. The MOSFETs are 12 x IPT015N10N5. We have tested both synchronous and asynchronus rectification (controlled by firmware, the DRV8350 was always in 6x PWM mode) with the same results, and PWM frequency has been 16kHz, 32kHz and 48kHz, in all cases we found the failure.
Unfortunatelly the mentioned thread, even though closed as "resolved" did not display a solution to this problem, this is why I am opening this new thread.