DRV8301: nFault pin keeps output low for 800µs

Adam Brooks

Prodigy 20 points

Part Number: DRV8301

I am working on a 3-phase bldc motor driver with DRV8301.

When starting the motor, the nFault pin keeps switching to low for 800us.

I find no error in Reg0.

What fault can cause the nFault pin to go low without latching the fault in Reg0 or Reg1?

Any fault can be reset automatically after 800us?

Thanks in advance.

over 6 years ago

0 Adam Sidelsky over 6 years ago

TI__Guru 65410 points

Adam,

Have you looked at "Table 5. Fault and Warning Reporting and Handling" in the datasheet?

Are you checking the OCTW pin as well?

Regards,

-Adam

0 Adam Brooks over 6 years ago in reply to Adam Sidelsky

Prodigy 20 points

Thanks for your reply.
Actually it's about my PCB layout.
After I place AVDD bypass capacitor closer to AVDD pin, the fault is gone.
It seems sensitivy to the resistance between AVDD and its bypass capacitor.

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DRV8301: nFault pin keeps output low for 800µs