> I've been under the impression that star grounds are more important with
> high currents, to make sure that you have consistent references. =A0It is
> important to understand where your high currents are- current across an
> impedance means voltage- which can cause your ground reference to change-
> which can lead to very weird outputs, particularly with respect to analog
> parts.

I've found that when using star grounds, if the star is imperfect and
there are some common tracks (and it is unlikely that you want or are
realistically able to bring every earth back to a single point with a
star (reasons for ground planes carol gently in background) then being
sure that high current or noisy star limbs don't common up with analog
low level limbs really helps. (or, conversely, when I DIDN'T give that
enough attention ... :-) ) .

Beating a design to death with applied common sense usually gets you a
fair bit of the way there.

Q: "Does this track carry large currents and/or processor or other
digital signals?"
A: "Yes."
Q: "Do they share any common return path?"
A: "Yes."
Q: "Why?"
A: "Um. Er."


  R

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