timingdrivenspacing Timing driven spacing check box in the GUI When timing

Timingdrivenspacing timing driven spacing check box

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-timing_driven_spacing (“Timing driven spacing” check box in the GUI) When timing-driven spacing is enabled, Zroute adds space between critical nets and nets that are parallel to them to reduce the intralayer coupling capacitances. By default, timing-driven spacing is not enabled.
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Chapter 8: Routing Using Zroute Setting Up for Routing 8-21 IC Compiler Implementation User Guide Version D-2010.03-SP2 To report the design-specific nondefault routing rules defined by the define_routing_rule command, use the report_routing_rules command. By default, this command reports all of the nondefault routing rules for the current design. To limit the report to a specific nondefault routing rule, specify the rule name as an argument to the command. icc_shell> report_routing_rules rule_name To output a Tcl script that contains the define_routing_rule commands used to define the specified nondefault routing rule or all nondefault routing rules for the design if you do not specify a routing rule, use the -output option when you run the report_routing_rules command. Specifying the Routing Layers IC Compiler lets you specify which layers can be ignored for routing and which layers are to be ignored for RC and congestion estimation. You can also specify the routing layers to use for specific nets (net layer constraints). By default, when you set a maximum routing layer, it is a hard constraint. You can change it to a soft constraint or you can allow the use of higher layers only for pin connections by setting the max_layer_mode common route option. This option applies to both ignored layers ( set_ignored_layers command) and net layer constraints ( set_net_routing_layer_constraints command). By default, when you set a minimum routing layer, it is a soft constraint. You can change it to a hard constraint or you can allow the use of lower layers only for pin connections by setting the min_layer_mode common route option. This option applies to both ignored layers ( set_ignored_layers command) and net layer constraints ( set_net_routing_layer_constraints command). Specifying the Ignored Layers To specify the ignored layers, use the set_ignored_layers command (or choose Route > Routing Setup > Set Ignored Layers in the GUI). By default, RC estimation and congestion analysis use the same layers as routing. To specify the minimum and maximum routing layers, use the -min_routing_layer and -max_routing layer options, respectively. If you use only these options, the same layers are used for routing, RC estimation, and congestion analysis. For example, to use layers M2 through M7 for routing, RC estimation, and congestion analysis, use the following command: icc_shell> set_ignored_layers \ -min_routing_layer M2 -max_routing_layer M7
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Chapter 8: Routing Using Zroute Setting Up for Routing 8-22 IC Compiler Implementation User Guide D-2010.03-SP2 IC Compiler Implementation User Guide Version D-2010.03-SP2 To use fewer layers for RC estimation and congestion analysis than those used for routing, use the -rc_congestion_ignored_layers
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