Hello all,

I have only done 1 and 2 layer boards, and I now have a project that
requires 4 layers.

It will be a fairly standard 4 layer board, 2 signal layers on the outter,
and power and ground planes on the inner.

My question is, when putting the caps in for the IC's on the board I have
2 options - as far as I can imagine they would both do the same thing, but
I wasn't sure if there was some benefit of doing it one way over another
as I have never done a 4 layer board before.

Normally, one would have a decoupling cap for each IC connected between
the Vcc and Vss pins.  My question is - do I need to connect this cap
directly to the vcc and vss pins of the given IC, or is placing the cap
near the IC and connecting it to the power and ground planes sufficient?
Technically it will be connected to the power and ground planes if it were
just tied to the pins, but I was wondering if there was some difference
I'm just not aware of by having it connected to the pins rather then to
the planes?

I hope I was clear on that.  I realize it may be a silly question, but I
am really not sure on which route would be the best since I really don't
see a difference, but I was hoping someone with more experience on 4 layer
boards might be able to clarify whether I am correct or wrong and possibly
why (if I'm wrong of course :).

-Tony

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