I keep getting faults on a a new batch of ESC boards based on the TI DRV8353RH & Infineon IPT020N10N3ATMA1. Please consider:
When starting a motor at 48V - 56V the DRV asserts a fault after sending a very brief PWM to the windings. Sometimes the motor buzzes for a second or so before the fault occurs. Sometimes it starts turning.
No faults occur when starting the motor at 30V. If motor is started at 30V and the VM increases to 48V or 56V no errors occur either. Also, when the DRV works, it works as expected.
The fault only resets after toggling the EN pin. Does this mean it's either VDS overcurrent, VSense overcurrent or Gate Drive Fault? We cannot find the issue.
It's very difficult to say when the "faulty" PWM-period occurs, this seems very random. Other phases do not display this issue. Also, the performance is very motor-specific. Some motors trigger the fault instantly, others just work.
A capture of phase B hi-side FET VS (purple), VD (green) and DRV nFAULT (blue):
Waveforms look similar on all half-bridges.
A capture of phase B hi-side FET VS (purple), VD (green) and DRV nFAULT (blue) at 20ns and 100ns :
MOSFET drain-areas on the top-layer:
MOSFET drain and source areas on the inner 2: This is the gnd-layer and my most controversial decision. I needed to increase the cooling areas underneath the FETS. Signals and waveforms look fine despite this.
The half-bridge layout of a previous, working, HW version:
The DRV layout of a previous, working, HW version:
3D-view of the previous, working, HW-revision as reference:
I really don't know where to look anymore. Please don't hesitate to ask for a specific capture if that would make it easier to help. I have a ton saved and could capture many more, I just did not want to clutter the post in advance.