DRV8244-Q1: Wake up failed after power-up, nFAULT pin jumps low

Hi team,

Here's an issue from the customer may need your help:

Device number: DRV8244SQRYJRQ1

After initial power-up, the customer tried the operation mentioned in the wake-up function in the manual and gave a pulse waveform approximately 220 microseconds after nSLEEP was asserted high, but the result was not expected (the outx dot bit was 0.38V, at this point the EN pin is set high, PH is set low.)  The nFAULT pin responds after the pulse waveform is given, but the nFAULT pin starts to pull low automatically after 150 microseconds and the waveform is shown in the following figure:

Test result: OTx spot bit is 0.38V with EN pin set high and PH set low. NFAULT is low.

Could you help look into this case? Thanks.

Best Regards,

Cherry