On Mon, Feb 16, 2004 at 01:09:19PM -0800, Richard Purdie enlightened us
thusly
>
> I have a CPU board with numerous IO connectors and I can't decide if I
> should be worried about ground loops or not when putting it into a
> metal case.
>
> The case will be grounded with incoming (low voltage) power. My main
> concerns are the audio line in (3.5mm jack), audio out (phono/RCA) and
> USB. Each comes from the CPU board with a ground line (or a screen
> with USB). Should the grounds/screen on each of the connectors
> electrically connect with the case or not?
>
> It would certainly make my life *much* easier if they could all
> connect to the case. I've tried researching this but what I read
> seems to conflict. Does anyone have any advice/experience?
>
I would keep analogue and digital grounds separate throughout, unite
them at one point, and earth that point to the case. If possible, I
would isolate the plugs from the case and run a ground wire.
Take great care with your mountings; they are a favourite weak point,
seem to attract damp, and don't rely on any techie to tidy them up the
way you want.
In a worst case analysis take continuous spikes being generated from a
fault coming through the smoothing to ground as current pulses. You
don't want that on your analogue!
--
With best Regards,
Declan Moriarty.
--
Author: Declan Moriarty
INET: [EMAIL PROTECTED]
Fat City Hosting, San Diego, California -- http://www.fatcity.com
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB CHIPDIR-L
(or the name of mailing list you want to be removed from). You may
also send the HELP command for other information (like subscribing).
