Homebrew PCBs

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