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AR# 21966

7.1.03 - Timing Analyzer/Timing - Clock Uncertainty Missing in timing report


General Description:

Some of the I/O paths driven by a DCM-based clock appears to be missing the DCM component of clock uncertainty. The reported uncertainty is ~25 ps when similar paths have ~205 ps. 205 ~ 50/2(SJ) + 120/2(DCM Jitter) + 120(DCM Phase). When is this going to be fixed?


This problem has been fixed in the latest 7.1i Service Pack available at:

The first service pack containing the fix is 7.1i Service Pack 4.

AR# 21966
Date Created 09/04/2007
Last Updated 01/18/2010
Status Archive
Type General Article