> 
> Eliminating 90 degree angles on traces does tend to reduce 
> signal degradations within the trace.  It also tends to 
> reduce crosstalk between traces (as in a bus) as well.  
> This is based on how the current distributes itself 
> in the ground plane.
> 

I tend to agree with Lee Richey (engineering mgr @ 3Com Corp, and respect high-
speed design lecturer and consultant) and James Blankehorn (SMT Plus president
and again, respected lecturer) who state again and again, VIAs and 90 degree
bends have little (theoretically) effect on high-speed designs.

Sure, with 90 degree lines they don't look quite as nice as 45s, but time-to-
market is an issue. I want a connection, first and foremost, at a particular
length, then make sure it's manufacturable. I could care less if it looks
pretty! I don't do analog designs, so I don't need special care for trace
"cosmetics".

And, if you still don't believe me, open you Sun sparc or you PC and check the
boards out. Then look in some of the current design mags. You'll begin to see
alot of design with 90 degree traces.

Just my thoughts.

Mitch Morey

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