DRV8303: Negative gate voltage during regeneration

Part Number: DRV8303

Hello to everyone,

I have a new issue with the above mentioned three phase driver.

I have an application where I use two legs of drv8303 to drive a reversible DC motor. In this application there's the real chance that this motor will be forced to move while the drive is turned off.  Here is what I see on the scope when I move the motor to a fraction of the nominal speed.

Green trace is HS_A

Yellow is GH_A

Pink is GH_A - HS_A

As you can see there's a negative VGH_DIF lower than the minimum absolute rating of the IC. And, of course, sometimes the IC is killed by this treatment.

I can't find any workaround, since it seems to me that vbus capacitors charging through the body diode of the high side mosfet is causing the presence of this voltage. Does it means i can't use DRV8303 in an application where i can expect some kind of regeneration into a turned off board?

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