Re: My continuing saga with power supply bypassing

On Sun, 29 Apr 2007 19:28:10 -0400, John Popelish <jpopelish@xxxxxxxx>
wrote:

a7yvm109gf5d1@xxxxxxxxxxx wrote:
Hi gang,
As you may know, we have a consultant offering his advice on bypassing
a power supply for a power-hungry ASIC that needs quiet power. (few
100 uVs of noise) It boils down to the "many values of caps" strategy.

So he has sent me a list of values, along with the fact that the
values must come in certain physical sizes. He has offered no part
numbers except to say choose the cheapest caps on Digikey. So I'm
creating the parts in our CAD system, but some cap values don't exist
in 0201.
(snip)

I have been puzzling out how I would connect several
capacitors as a bypass, without eating up lots of real
estate, keeping the resonances low Q and the impedance of
the ground currents very low. The best I could come up with
is posted to alt.binaries.schematics.electronics.

I am interested in how it could be improved, in case I ever
try this technique.

Is the intent to lowpass the power trace that enters at the top, for
some load at the bottom?

John

.

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