Question re: about current control schematic

Jon, one limitation of this circuit which you point out is the absence
of the ability to vary the current delivered depending on the number
of phases switched on. Is there any reason this could not be added
with different VR 1 values switched in or out with a 4066 by
appropriate logic which responded to number of phases turned on?

Grant

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:
>[snip]
> But, finally, this is a HORRIBLE circuit! It runs the motors as
> unipolar, and makes no provisions for individual control of the
> current in each phase! It will have HORRIBLE performance at
> higher speeds, and will likely blow T1-T4 with any motor larger
> than the ones in floppy drives, since no provision is made at all
> for the inductive energy in the windings. I'd drop it and look for
> a better circuit right away.
>
> Jon