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Date: Thu, 23 Apr 2015 23:57:52 +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 04/23/2015 11:30 PM, Rob Butts wrote:
> One last question regarding steppers.
>
> I am looking at the Pololu DRV8825 stepper motor drive rated for 1.5A
> without a heatsink or 2.2A with cooling.  The nema 23 steppers that
> I've found are mostly 2.8A.  Is that the coil max amp rating or what
> it draws when driving it (clearly I know little about steppers)?  I'm
> guessing this will overload the DRV8825.
> ​


that would be the max amp rating, I guess (that or the current which
guarantees the nominal holding torque, but I know from experience that a
stepper rated for 350 mA will get pretty hot and jumpy and noisy when
driven with 600mA - found this out when testing some drivers I made a
while ago, also DRV8825 (it's a nice little chip); unlike my board, the
Pololu drivers are made with thicker copper and probably have the back
of the board turned into a heatsink, as the datasheet recommends