DRV8312: Motor Driver FET Failing Closed

Part Number:DRV8312

During multiple operation modes, the DRV8312 fails with the low-side FETs closed. This happens during regeneration events as well as normal operation. This is a complex problem and I have documented a few operating conditions.

For config, the motor driver is connected to a 48V power supply, being driven by a micro-controller. It is configured for cycle-by-cycle current limiting with a 6.9A limit.

The failure occurs when resets are both on and off.

Our switching frequency is 20kHz and we reduced the maximum duty cycle to 90% (giving plenty of time for the bootstrap to recharge) and still observed the original failure condition.

As this is a highly complex issue, I imagine there are many variables to clarify. I have attached an image of my schematic to help with any obvious issues.