Friday, June 17, 2016

specifying the timing derating factors

Timing derating factors model the effects of varying operating conditions by adjusting the delay values calculated for the individual timing arcs of a block. By default, the timing derating factors are 1.0 and the tool does not adjust the calculated delay values.
To set derating factors, use the set_timing_derate cmd and specify the following information:
-- the derating factor
-- whether the derating factor is for early or late delays by using the -early or -late options.
Optionally , you can apply the derating factor to
-- Specific leaf-level instance, hierarchical instance, or library cell by specifying the object.
    By default, it applies to the current block.
--Rise or fall delays only by using the -rise or -fall options.
    by default, it applies to both rise and fall delays.
-- clock or data paths only by using the -clock or -data options
    by default, it applies to both clock and data path.
-- net delays, cell delays, or cell timing checks by using the -net_delay, -cell_delay, or cell_check option. by default, it applies to all three.
-- A specific cornet by using the -corners option.
By default , it applies to the current corner.
The following example reduces all minimum delay by 10 percent and increase all maximum delays by 20 percent for the current cornet:
icc_shell> set_timing_derate -early 0.9 -late 1.2

To report the derating factors, use the report_timing_derate cmd. By default, the cmd reports the derating factors for all corners. To report the derating factors for specific corners, use the -cornet option.

To reset the derating factors to 1.0, use the reset_timing_derate cmd. By default, the cmd resets the derating factors for the current corner for the current block and all its instances. To reset the derating factors for specific corners, use the -corners option. To reset the derating factors for specific objects, specify the objects.




2 comments:

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  2. If you do it in some more practical way...it will more helpful

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