The following sections describe how you perform different types of leakage and

The following sections describe how you perform

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The following sections describe how you perform different types of leakage and dynamic power optimization on multicorner-multimode designs. For details on multivoltage, multicorner-multimode design optimization, and the UPF flow for the multivoltage, multicorner-multimode design optimization, see the Power Compiler User Guide . Optimizing for Leakage Power Figure 10-37 on page 10-167 shows how you set various constraints on different scenarios of a multicorner-multimode design. Typically, in a multicorner-multimode design, leakage power optimization and timing optimization are done on different corners. Therefore, the worst case leakage corner can be different from a worst case timing corner. To perform leakage power optimization on specific corners, set the leakage power option on specific scenarios of the multicorner-multimode design by using the set_scenario_options command as follows: set_scenario_option -scenario S1 \ -setup false \ -hold false \ -leakage_power true Note: The get_dominant_scenarios command is not supported in Design Compiler Graphical.
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Chapter 10: Using Design Compiler Topographical Technology Optimizing Multicorner-Multimode Designs in Design Compiler Graphical 10-167 Design Compiler User Guide Version F-2011.09-SP2 Figure 10-37 Setting Different Constraints on Different Scenarios Note the following points when you optimize for leakage power in multicorner-multimode designs: Define the leakage power option on specific scenarios targeted for leakage power optimization. Leakage and timing optimizations can be performed concurrently across multiple scenarios. The worst case leakage corner is different from the worst case timing corner. Do not use the set_leakage_optimization command inside a scenario. This command is supported only for non multicorner-multimode designs. Note: The set_dynamic_optimization command enables dynamic power optimization on all scenarios of a multicorner-multimode design. Dynamic power optimization is scenario-independent. When you specify multiple ways of power optimization, the tool uses the following order of priority, highest to lowest, irrespective of the order in which you have specified these commands: 1. set_multivth_constraint 2. set_scenario_options -leakage_power 3. set_leakage_optimization true or set_dynamic_optimization true
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Chapter 10: Using Design Compiler Topographical Technology Optimizing Multicorner-Multimode Designs in Design Compiler Graphical 10-168 Design Compiler User Guide F-2011.09-SP2 Design Compiler User Guide Version F-2011.09-SP2 In the following example, the leakage optimization specified on the entire design is ignored or disabled and the leakage option specified on each scenario is honored. Leakage optimization is performed only on scenario_1 and scenario_3: set_leakage_optimization true set_scenario_options -scenarios {scenarios_1, scenarios_3} \ -leakage_power true set_scenario_options -scenarios {scenarios_2, scenarios_4} \ -leakage_power false The following example script shows how to create a scenario and set the leakage power
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