Re: L297/L298 Question

John:

Thanks for your reply. I was eventually able to fish
an Ap Note out of the ST site that explained that
turning off the entire H-bridge (inhibit/enable)
causes the current through the coil to delay faster
than just turning off the top of the H-bridge.
I got this out of ST's "Applications of Monlithic
Bridge Drivers" application note.

As near as I can tell, for higher rotation rates
out of the stepper motors (inhibit/enable) chopping
is the way to go.

Again, thanks,

-Wayne

--- In CAD_CAM_EDM_DRO@yahoogroups.com, John Johnson <johnatl@m...> wrote:
>
> According to ST, the maker, phase chopping is good for
> unipolar motors, and inhibit(enable) chopping is better
> for bipolars.
>
> Search for L298 or L297 and the word 'application' on
> the ST site for many more circuit design ideas.
>
> http://www.st.com/stonline/products/literature/an/1650.pdf
>
> Regards,
> JJ
>
> On 18-Nov-2005, at 14:01, Wayne C. Gramlich wrote:
>
> > I notice that the L297/L298 combo has the ability to
> > be operated in two basic modes. When the Control
> > line of the L297 is low, the L297 chops using the
> > Enable pins on the L298. When the L297 Control line
> > is high, the L297 chops using the Input lines on
> > the L298.

[snippage]