DRV8316: DRV8316 every 5ms trigger nFault signal, nFault signal keep low about 20us

Tool/software:

hi, we are uing DRV8316T hardware mode to driver motor, we have not connet motor phase wires.

On oscilloscope, we have see nFault signal erery 5ms and last 20us，Do you know the possible reasion？thanks a lot!

our schematic is below

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