DRV8350R: SPI power up and sequence issue

Bruno,

Thanks for posting on the MD forum!

1. Will the MCU be driving any signals that the DRV will be connected to?

2. There is no issue with power sequencing from the SPI side of things.

Which PWM mode will you be using?

Regards.

-Adam

Adam,

Yes, MCU will be driving some signal without DRV power up. 

We are using center-aligned modes in the PWM timer. 

Best Regards,

Bruno Duan

Bruno,

I would not suggest driving any signals into the DRV when the device is powered off.

I was asking about the DRV PWM mode, are you providing 1, 3, or 6 PWM inputs to the DRV?

Regards,

-Adam

Adam,

1. Will it cause any problems if we did driving some signals? 

2. We are providing 6 PWM inputs into DRV. 

Best regards,

Bruno Duan

Bruno,

The device can handle up to the ABS MAX ratings even when the DRV is unpowered so you should not see any issue.

If you would like some additional safeguard I would use a small series resistor in the path of the signals that will continue to run when the DRV is off. This would prevent the case where an ESD inside the DRV may conduct.

Regards,

-Adam