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.
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 email@example.com I'll take a look and possibly be able to provide more insight.
Yes it was the pull up!
I have enabled pull up mode on the micro's port pin and it's working fine now.
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