I've made a handy dandy schematic for this available on my
website: http://www.excelsus.com/~remy/DualStepperSchematic.pdf

That schematic shows one half of the 4 steper circuit I am
planning to build on one PCB.  When I do, I will separate power
supplies, use a DIP 1k resistor array between the PIC and darlingtons, and
put bypassing on the logic power/gnd leads.

Thanks for all your assistance so far. :)

Gustaf
> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Rick C.
> Sent: Saturday, February 28, 2004 1:30 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [EE:] Release of magic smoke
>
>
> Never rely on internal diodes to do the job of external snubbing.
> There's no way
> the substrate of the ULN device can handle the spike supression
> of any motor.
> The internal diodes are there as a last resort, not the first
> line of defense.
> ~Rick
>
> "Gustaf J. Barkstrom" wrote:
>
> >   I will rely on the internal kickback protection diodes.
> > Gustaf
> >
>
> --
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--
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