Question to IBIS Reflector

IBIS folk:

        I am curious how one does rise and fall time measurements
using packaged parts. The spec calls for these ramps to be measured
on I/Os with no loading, but this implies wafer-level measurements
which are less than ideal from a noise standpoint. One can use a
high-impedance probe on packaged parts but then one gets a few pF
and a few nH of LC network. In programmable logic it is almost
imperative that a tester be used, as the I/Os must be programmed
into their appropriate modes.

        My guess is that this will cause little effect on the
rise and fall times, but is this correct? Is this something that
really must be SPICEd?
 
Received on Wed Oct 30 11:45:07 1996