Typically the biggest concern I see is not in clock rate, but in edge
speed, the two do not necessarily correlate.
What I mean, is some of our designs vary in clock speed but have a
consistently very fast edge rate. The result of the field created by the
fastest harmonics in the signal can be spurious noise on adjacent
signals dependent on the dielectric material (and of course pitch, and
spacing to a GND plane).
We are trying to help our customers justify specifying GETEK v. FR-4 v.
Cu-Clad, etc. by comparing propagation and crosstalk signatures on a
number of test structures. I would also be interested in anyones
experience in a similar application.
Thanks,
Brett
-- ------------------------------------------------------------------------ Brett Grossman __ ___ Intel Tooling Operations __ /\ \__ /\_ \ Phone: 408-765-2619 /\_\ ___\ \ ,_\ \//\ \ Fax: 408-765-2518 \/\ \ /' _ `\ \ \/ __ \ \ \ email: [email protected] \ \ \/\ \/\ \ \ \_ /'__`\\_\ \_ \ \_\ \_\ \_\ \__/\ __//\____\ \/_/\/_/\/_/\/__\ \____\/____/ The views expressed are my own. \/____/ ------------------------------------------------------------------------