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AR# 15573

5.1i Speed Files, Virtex-II/Virtex-II Pro - Differential pairs do not match timing


Keywords: differential, pairs, I/O, IO, match

Urgency: Standard

General Description:
I run my design through timing and see that my differential pairs do not match. The N and P sides are different values, but they should be the same.


The input adjustment data is missing from the speed files for differential I/O standards with termination (input side).

This problem is fixed in the latest 5.1i Service Pack, available at:
The first service pack containing the fix is 5.1i Service Pack 1.

AR# 15573
Date Created 09/09/2002
Last Updated 03/06/2005
Status Archive
Type General Article