[sdiy] Analog & Digital Ground

[Ian Fritz]

At 10:46 AM 4/11/06, Harry Bissell Jr wrote:
>Gaarrrr Ian, you should know better than that :^P

Oh, probably.


>If the example you're thinking of is Fig 21... this
>would be good for independant circuits in the same
>rack but i think it would be more trouble when you
>start to interconnect them.  A signal originating from
>one board has to reference through two beads (extra
>inductance) before returning to the source of the
>current. I think it will increase the signal
>distortion

Yes, I use fig 21, except to isolate switching and low level sections on a 
given board. Signal distortion?  The beads only work at RF.

>I think that careful PCB layout and routing of traces
>to maximize capacitance and minimize inductance
>(parallel power and ground traces) and proper
>decoupling will do much more than the beads...

In my experience the beads have killed spikes that extra bypassing 
doesn't.  But maybe my layout wasn't good enough.

   Ian