Re: Allegro 3977

--- In CAD_CAM_EDM_DRO@y..., "mariss92705" <mariss92705@y...> wrote:

> I would like to caution anyone trying to build a drive with this or
> any other monolithic type power IC to breadboard it on a printed
> circuit board. Do not try to "wire" it up on a perforated

Yeah... Ever wonder if most of those power driver IC packages are
*designed* so that they don't fit easily on a perfboard? Saves the
applications engineers from explaining to people like me why my
breadboard lashup won't work.

Seriously, I've been fooling around with a first attempt PCB for this
beast, but I've never seen such an ugly pinout. What the heck is the
STEP input doing way up in the left hand corner??? Most people want
to bring out the motor phase lines to a connector right next to each
other, so where do they put them on the chip? One on each corner, as
far away from each other as possible! No idea how to do this without
a bunch of vias in 2+ amp current paths.

Sorry for the whining, I suppose that pin the locations are a result
of the highly optimized wafer layout...

- Tom S.