On Fri, 25 Aug 2006 19:40:50 +0200, Adrian <
adicont2@...> wrote:
>
> "When doing ground layout i like to think in voltage drops"
> You refer to traces voltage drops?
> Adrian
No, i imagine where the currents go and if the voltage drop they cause is
going to upset another circuit.
If voltage drop is not seen by a sensitive part of the circuit it does not
matter.
The reason for star ground is that all the voltage drops are in parallel
to each other, so none can be seen by any other part of the circuit. But a
star branch to each and every connection is not always possible. So you
must think if the voltage drop of one branch will be a problem for another
branch, the drops will now be in series. You do not want "noisy" drops
from digital circuits to be seen by a analog component that is sensitive
to the ground noise.
ST