Had a similar problem with an op amp circuit - fixed by having a 100n
capacitor across the opamps +/- supply pins i.e. between +5v and -5v supply
pins.

The transit I was suppressing was a pump start up that caused a transit on
the incoming 230v supply.

But I assume you have caps across all supplies right next to all of your
chips.

*************************************************
Roy Hopkins   :-)

Tauranga
New Zealand
*************************************************

----- Original Message -----
From: "Ian Rozowsky" <roz@CENTSYS.CO.ZA>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, June 22, 2004 10:43 PM
Subject: [EE]: Supressing fast transients


> Hi all
>
> I'm currently putting an inverter design through compliance testing, and
> have a problem with fast transients on the incoming power lines. I've
added
> common mode chokes and Y-cap to address conducted emissions, but
electrical
> fast transients are getting through, and dirupting operation of the
> processor (16F870). I'm looking as some series inductors as a solution,
and
> was wondering if anyone on the list has had similar experiences, and how
> they were resolved. Input currents are around 5A.
>
> Regards
>
> Ian Rozowsky
> R&D Director
> Centurion Systems (Pty) Ltd.
> Box 506 Cramerview 2060 South Africa
> roz**@centsys.co.za
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sending||
> http://www.centsys.co.za
>
>
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