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AR# 31152

14.x Timing Analysis - VALID keyword is not applicable to the OFFSET IN AFTER constraint

Description

When the VALID keyword is applied to the OFFSET IN AFTER constraint line, both setup check and hold check should be performed.

When performing timing analysis, the setup check requirement is the same as expected, andthe hold check requirement should be (Tvalid- Tsetup_requirement).In the timing report, it has the same value for setup and hold which is incorrect.

Solution

Timing Analyzer is incorrectly calculating the hold check requirement.

For the time being, you could use the constraint OFFSET IN VALID BEFORE instead, which can perform setup and hold check correctly. Please modify the relevant constraint appropriately.

AR# 31152
Date Created 06/11/2008
Last Updated 12/15/2012
Status Active
Type General Article
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