how to use best case, worst case, typical case of a technology

[onion2014]

hi all, i have a question about dc command: set_operating_conditions -min BESTCASE -max WORSTCASE

i notice that there are three .db files under the synthesis library directory, which are XXXbc.db XXXwc.db and XXXtc.db respectively. I browse through the respective .lib files, they are the same technology library but with different operating conditions. If I want to use set_operating_conditions command, I need to use the bestcase and worstcase, which are in different .db files.

So should I include two .db file in my target_library?

thanks in advance.

 

[rca]

You need first to know the range of voltage in which your application will works.
In simplified synthesis run, you select the most difficult corner, means which one is most difficult to reach the setup during the synthesis step.
During the PnR steps, you could run in MMMC mode, means multiple mode, and multiple corner, and check the setup and hold for how many corners you want.

 

[onion2014]

so for safe, i use the xxxwc.db as target library and then include both the xxxwc.db and xxxbc.db in the link_library, and then in the dc script, I use set_operating_conditions -min BESTCASE -max WORSTCASE? if so, dc will check timing using either bestcase or worstcase, right? but finally, dc will generate gate level netlist using the target_library, right?

thanks.

You need first to know the range of voltage in which your application will works.
In simplified synthesis run, you select the most difficult corner, means which one is most difficult to reach the setup during the synthesis step.
During the PnR steps, you could run in MMMC mode, means multiple mode, and multiple corner, and check the setup and hold for how many corners you want.