DRV8825 fault pin

richard markham

Prodigy 110 points

Other Parts Discussed in Thread: DRV8825

We have just started using the DRV8825 in a new design.

The fault pin seems to always be set low.

There are no output shorts.

VM is 24V and the charge pump output is 34v.

The fault pin is low during and after reset, regardless of current limit setting, step mode, decay mode and even with no motor connected.

over 11 years ago

Jose Quinones over 11 years ago

TI__Expert 7455 points

Hi Richard,

Is there a pull up resistor at the nFAULT pin? The output is an open drain, so you will need one. I cannot think of what else may be going on, but if you send me an schematic at jquinones@ti.com I'll take a look and possibly be able to provide more insight.

Best regards,

Jose Quinones

richard markham over 11 years ago in reply to Jose Quinones

Prodigy 110 points

Hi Jose,

Yes it was the pull up!

I have enabled pull up mode on the micro's port pin and it's working fine now.

Many thanks.

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DRV8825 fault pin