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Date: Fri, 24 Apr 2015 00:44:27 +0300
From: Sabin Iacob <iacobs AT m0n5t3r DOT info>
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To: geda-user AT delorie DOT com
Subject: Re: [geda-user] Stepper driver issues
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Reply-To: geda-user AT delorie DOT com

On 04/24/2015 12:11 AM, Rob Butts wrote:
> I'm wondering if I can use the DRV8825 to drive a nema 23 2.8A stepper
> without cooking the DRV8825.​

the worst case is that you won't get the maximum rated torque out of the
motor: these drivers operate in current mode - you configure the maximum
current somehow (DRV8825 has a pot, the chip that died on you has a
resistor voltage divider in the datasheet schematic), and depending on
the microstepping setting you either get one or several steps between
zero and the maximum set current, the motor can't "draw" more and kill
your driver unless the current limit you have set exceeds the limits of
some component (sense resistor, driver chip's thermal capacity, etc.).