RE: [SI-LIST] : Ground gap problem

Ingraham, Andrew (Andrew.Ingraham@compaq.com)
Tue, 4 May 1999 22:39:59 +0800

> >3. connect a cap to the IC power and ground pins (using traces) AND
> connect
>the
> >cap to the planes (using via's).
>
I think I misread this the first time (caffeine hadn't taken full effect
yet).

My comments before were about yet another choice: connect IC power or
power+ground pins to planes using traces, and then connect the cap to the IC
end of those traces.

Choice #3 as stated may not be good because the traces isolate the IC from
all HF bypassing; both the planes and the capacitor are on the other end of
the traces. But if your IC generates mega power noise, and doesn't care if
its power pin is noisy or not bypassed, then choice #3 could be acceptable.

Andy

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