Re: 16-bit 625Mbaud XGMII
Mike Jenkins wrote:
> Jaime, et al,
> For what it's worth, I would like to remind everyone who may have
> lost sight of it, the best way to eliminate the switching noise
> of the XGMII is to absorb it into the chip. That is, integrate
> the XGXS and the MAC into one chip, solving not only that
> switching noise issue, but yielding the pin count benefits
> of the XAUI interface, as well.
> I know there is still a migration toward that goal to contend
> with, but the switching noise issue is very likely more
> shortlived than the 10G standard.
I had exactly this in mind when I insisted that the electrical
specs of the (optional) XGMII should be carefully defined so
as to give a fair chance of success to anyone planning on
exposing/implementing this interface.
I do not share the optimism of those betting on an
early (or late) integration of the MAC with the PHY.
The experience in this area is not very convincing
and many times in the past it was more effective to have
two separate chips, one for the MAC and the other for
the PHY (PCS/SERDES).
Jaime E. Kardontchik
San Jose, CA 95131