> Would you believe in connecting three points 0.2" apart with
> > 0.1" trace, I can get a 2dB improvement in switcher output noise by
> > connecting them in the right order, as opposed to a triangular "blob"
> that
> > connects all three?
>
>    Can you comment a little more on this ? Sounds quite interesting....


In this particular case, I was dealing with the output of a 300kHz switcher.
The node in queston connected the output diode, an electrolytic cap, and an
inductor, which fed the next stage.  I knew that routing it in the order of
diode-cap-inductor was best, and diode-inductor-cap would be worse, but I
was curious what the "blob" would be.  So, I waited till the boards came
back, and pulled the traces off one and made the blob with braid and
solder.  I checked the noise on the output of the supply with a spectrum
analyzer, on the same board, before and after.  2dB worse for the blob.

There was a small value cap right across the electrolytic terminals,
probably a 0.1, but I don't remember for sure.
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