Re: 8b/10b and EMI
Amid all the concern about EMI, I haven't seen mentioned a (perhaps
small) improvement that will take place with adoption of the XAUI
(nee Hari) electrical spec. In addition to the lower signal levels
(6-8 dB), the change to 50 ohm impedance will make practical the
use of stripline (as opposed to microstrip) PCB traces for the
high speed lines. That is, the offending signals can now be
buried between power planes, rather than placed on outside signal
layers (as dictated by 75 ohm impedance). This change ought to
considerably reduce emissions....FWIW.
Mike
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Mike Jenkins Phone: 408.433.7901 _____
LSI Logic Corp, ms/G715 Fax: 408.433.7461 LSI|LOGIC| (R)
1525 McCarthy Blvd. mailto:Jenkins@xxxxxxxx | |
Milpitas, CA 95035 http://www.lsilogic.com |_____|
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