4 layer pcb and decoupling capacitor

Hi everyone :slight_smile:
I would have a question about a 4 layer pcb with 1 layer ground and 1 layer power.

I was under the impression that when using an entire layer for power and ground, I wouldn’t need any additional traces to connect power to my components. But how does that work for a decoupling capacitor? If it’s not placed directly between the power source and the component’s power pin, how does it actually help? Also, if I have multiple decoupling capacitors, don’t they just add up across the whole power plane?

Or in this case I would need to route the power from capacitor to the component?

Please read this:

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When placing ground and power zones you should ensure (may be change KiCad default settings) to allow this zones to leak between your IC pads. In such case you can think of these zones as being close to continuous copper fill.
No track will give you smaller connection impedance than copper fill.
The other case is that you ask the question like decoupling capacitor position is predetermined and cannot be changed while it should be better positioned to minimize total length between its pads and IC pads.

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