For OFFSETs with both positive and negative edge flip-flops, TRCE incorrectly calculates slack for negative-edge flip-flops. This causes problems with the correlation of Trace and PrimeTime simulations.
TRACE calculates offset slacks for two-phase clocks by basing the calculation on the respective edges. PrimeTime, on the other hand, bases its slack calculation on only the rising clock edge for both positive- and negative-edge flops.
To remedy this issue, create a group and OFFSET it for the positive set of flip-flops; create another group and OFFSET it for the negative-edge flip-flops.
This issue will be fixed in the next major software release.
AR# 11766 | |
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Date | 01/18/2010 |
Status | Archive |
Type | General Article |