Re: Low cost - EAS microstepper driver

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "v_fong" <v_fong@y...> wrote:

>
>
> Hi Fred,
>
> We came to that conclusion when we built our drivers a while back.
> Micro stepping is really the best way if you wish to use stepper
> motors. If you are able to solder, then consider building the
> controllers. We looked everywhere at the time for an inexpensive
> micro stepper setup. We ended up building them instead and now sell
> the bare boards. I design circuit boards for a living so these
> boards are very high quality and the design has proven to be quite
> reliable.
>
> Kin
>
> http://www.embeddedtronics.com/

Hi Kin,

The LMD18245 has a manufacturers rating of 3amps and 55 volts. but
the Xylotex will smoke if someone tries to run it at the 2.5 amp and
35 volt rating.

Makes me wonder if the chip can be used at the rull rating in this
appilcation ?

As Mariss has pointed out, the back EMF can spike and kill things in
circuits unless the circuit is de-rated, or unless there is some
serious protection.

Have you tested this at it's maximum ?

I think the reason I shyed away from your unit was that the h-bridge
chips are so prices. at $26.00 for a pair for one axis drive is not
as innexpensive as us cheap bas_ _ _ds want.

Dave