RE: [SI-LIST] : Worst case VI curve for PCI spec a reality?

Andrew Ingraham (Andrew.Ingraham@digital.com)
Tue, 21 Apr 1998 16:43:03 -0400

D. C. Sessions wrote:

> the PCI pullup spec for 5v has a *minimum* short-circuit Ioh of 44mA!
> Pumping that much current out of a 3.3v pullup without 3.3v clamping
> is fer-sher begging for disaster. OTOH, staying within the 12-24mA
> range for 3.3v (no, PCI doesn't have a max but 2:1 is achievable and
> weak is better) keeps ringback within reason.

Where do you get this (implied) 12mA minimum short-current Ioh for 3.3v
PCI ?

Last I looked, the minimum Ioh curves for 3.3v and 5v were almost on top
of one another. The big difference is in the pulldown curves.

Just out of curiosity, how do you folks deal with drivers that are
technically, no, blatantly non-compliant, even if it makes them work
better? If someone asks if your drivers comply with the PCI spec rev
2.1, do you admit that they don't? Do you advertise them as meeting the
spec?

Regards,
Andy Ingraham