CRPR Benefits in setup/hold analysis

To remove pessimistic value to become more realistic.

pt_shell> set_operating_conditions -analysis_type \
on_chip_variation -min MIN -max MAX
pt_shell> set_timing_derate -net -min 0.78 -max 1.00

For setup time analysis clock launch path is 100% worst case max path analysis and capture path is 78% min path analysis .

During setup analysis U1 will have 2 different delay values (common path for max and min (launch / capture analysis ).

To remove this pessimism launch path extra added delay get removed in capture path to get more realistic value .(because for setup analysis capture clock path is always min so it can’t be max path and extra added value in data path launch clock max analysis should be removed )

the setup check considers that cell U1 simultaneously has two different delays,
min= 0.64 and max= 0.80
resulting in a pessimistic analysis delays in the amount of 0.16.

Comments

GBA vs PBA

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MCMM

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