Re: gEDA-user: analog/digital partitioning

[Stefan Salewski <mail@xxxxxxxxxxxx>]

On Thu, 2010-07-22 at 02:13 -0400, gene glick wrote:
> I'm throwing this out to the list for opinions. . .
> 
> This design has mixed analog and digital circuits.

I do not know much about that, but I have seen a few discussions about
that topic in Internet. My conclusion: General discussion makes not too
much sense. You have to show your schematic and intended layout to smart
experts, than they can tell you how to improve it.

Often stupid partitioning of GND in digital and analog can generate much
trouble, so one single low impedance ground plane can be a simple and
not too bad solution.

For my DAD/DSO board I used a 4 layer board  with one ground plane,
divided into analog and digital part, joined near the ADCs. I think that
should be OK, but radiated noise (by air) may be a problem, ie. from
FPGA and switching voltage regulators to analog amplifiers. So I have to
shield the sensitive analog amplifiers by a tin cup. I think I will
build the board in a few months, so I will learn more about noise
coupling.

Best regards

Stefan Salewski





_______________________________________________
geda-user mailing list
geda-user@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-user