Re: PCB Impedance Control


Clearly putting a bypass cap at every via is impractical, and if you re-read
my post, that is not what I suggested. However, I stand by my recommendation
that in places where many nets and/or critial nets change reference planes,
a bypass capacitor nearby is important. Clearly, a single capacitor, perhaps
connected with multiple vias to the planes, can be shared by many signal
vias, as it will have a lot more capacitance than, for example, the planes
can provide.

Then I should be able to compute/estimate the value of "nearby"
and the size of the cap needed.

--
These are my opinions, not necessarily my employer's. I hate spam.

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