Help identifying a capacitor

[Tony Duell]

> Get the cap as close to the chip as you can: think of the trace as a
> (really low resistance) resistor: the resistance PS-to-cap is is much
> larger than resistance cap-to-chip and bingo! low-pass filter.

Actually, it's the inductive reactance of the trace/PSU connections 
that matters here. With high-frequency signals -- this doens't mean a 
high clock rate necessarily, it means a fast ris-time edge -- you can 
get significant voltage drop from very small 'inductors', like the 
connction from the chip to the PSU.

-tony