Joel Koltner wrote:
This is the first cut of the production department's layout for this switcher.
I saw "first cut" because IMO it needs some serious adjustment -- with the
most obvious problem being the distance between L3 and C87. This is an
8-layer board (don't ask), and both ground and the output of the switcher
("Vcore") go to their own dedicated planes whereas the switcher's input
("VBAT") is a larger copper pour on another layer. (I've turned off the
layers other than the top as none of the switcher's nets are routed on them
and they make for a considerably messier plot... C28 and C30 are decoupling
the power pins on a connector that's on the bottom side of the board, if
anyone's curious.)

Critiques are always welcome!


The distance to C87 isn't so bad since you wrote that this node is now
on a full plane. So it has lots of local capacitance to the ground
plane, hoping they are adjacent. Plus a really low "trace" impedance.

Just fire it up and see how it performs.

--
Regards, Joerg

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