Part 4 – Constraints Optimization
Constraint Efficiencies
Constraint Sets
These are reusable groups of electrical constraints.
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Implementation in Constraint Manager:
ɢ Open the Constraint Manager and navigate to the "Electrical" category
ɢ Navigate to any worksheet, like Routing > Wiring then right click on the design name and select "Create Electrical CSet"
ɢ Define constraints for relevant parameters depending on your worksheet category (like Topology Schedule, Vias,
impedance, Total Etch Length, etc.)
ɢ Apply the EC Set to specific nets or net classes as needed but in the Net folder within the respective constraint domain
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Benefits:
ɢ Ensures consistent electrical rules across multiple designs
ɢ Simplifies management of complex electrical constraints
ɢ Reduces time spent on constraint setup for new projects
ɢ Ensures consistency across different designs within an organization
Modular Approach To Constraint Management
Applying constraints in a layered, Venn diagram-like structure for flexibility and ease of management
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Implementation in Constraint Manager:
ɢ Create base-level constraint sets for general rules
ɢ Define more specific constraint sets for particular design areas or net classes
ɢ Use the constraint priority system to manage which rules take precedence
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Benefits:
ɢ Provides flexibility to apply general rules with specific exceptions
ɢ Simplifies management of complex rule interactions
ɢ Allows for easy visualization of constraint hierarchy
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OrCAD X Constraint Management Guide
