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worst operating conditions for typical library.

gops
I have 3 different libraries for typical, worst and best conditions. I'm using RTL compiler for synthesis purpose. I have used typical library for synthesiszing and obtained the synthesized netlist. But i need to analyse the same netlist under worst operating conditions. some one please tell me how to do this.
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  • If you truly want to analyze the design with the typical .lib and specify which operating condition within that typical .lib should be used for timing purposes, you can use the "setOpCond" command to inform the tool that the default operating condition in the .lib should not be used and to instead use a different operating condition.

    *However* in my years of working with Encounter I have *never* used this command. The reason for this is because it is common to use the slow.lib which has only a single operating condition for worst case timing. You mention that you have 3 different timing libraries- you would know whether your slow.lib has multiple operating conditions if you open it up and search for strings like this:

      /* operation conditions */
      nom_process     : 1;
      nom_temperature : 125;
      nom_voltage     : 1.62;
      operating_conditions(slow) {
        process    : 1;
        temperature    : 125;
        voltage    : 1.62;
        tree_type    : balanced_tree
      }
      default_operating_conditions : slow;

    In this example I've posted above, the slow.lib has only 1 operating condition: "slow" and it is also specified as the default.

    If you look in your .libs and see similar, I believe you would want to use your slow.lib for worst case timing. However, if you do indeed see multiple operating conditions within each of the .libs you would want to use setOpCond to instruct the tool which operating condition should be used for setup timing.

    Hope this helps,
    Bob

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  • If you truly want to analyze the design with the typical .lib and specify which operating condition within that typical .lib should be used for timing purposes, you can use the "setOpCond" command to inform the tool that the default operating condition in the .lib should not be used and to instead use a different operating condition.

    *However* in my years of working with Encounter I have *never* used this command. The reason for this is because it is common to use the slow.lib which has only a single operating condition for worst case timing. You mention that you have 3 different timing libraries- you would know whether your slow.lib has multiple operating conditions if you open it up and search for strings like this:

      /* operation conditions */
      nom_process     : 1;
      nom_temperature : 125;
      nom_voltage     : 1.62;
      operating_conditions(slow) {
        process    : 1;
        temperature    : 125;
        voltage    : 1.62;
        tree_type    : balanced_tree
      }
      default_operating_conditions : slow;

    In this example I've posted above, the slow.lib has only 1 operating condition: "slow" and it is also specified as the default.

    If you look in your .libs and see similar, I believe you would want to use your slow.lib for worst case timing. However, if you do indeed see multiple operating conditions within each of the .libs you would want to use setOpCond to instruct the tool which operating condition should be used for setup timing.

    Hope this helps,
    Bob

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