Constraint Definitions

The Virtuoso Space-based Router constraints are grouped by category. Each constraint description includes a definition, a Quick Reference Table, descriptions and examples for parameters and value types. All distance measurements are in user units, and areas in user units², unless otherwise noted.

The constraints are grouped into the following categories.

• Antenna Constraints
• Area Constraints
• Clearance Constraints
• CMP Constraints
• Density Constraints
• Extension Constraints
• Length and Width Constraints
• Miscellaneous Constraints
• Mixed-Signal Routing Constraints
• NumCut Constraints
• Overlap Constraints
• Placement and Alignment Constraints
• Routing Constraints
• Spacing Constraints
• Via Construction Constraints
• Wire Widening Constraints

Quick Reference Table

The quick reference table for each constraint lists the following:

• Constraint Type
  Identifies the constraint as one of the following types: Simple, Layer, Layer pair, or Layer array, as described in Constraint Objects.
• Value Types
  Identifies the legal value types for the constraint as described in Constraint Value Types.
• Database Types
  Specifies where the constraint is stored: design or technology database.
• Scope
  Identifies where Virtuoso Space-based Router looks for the value of the constraint, based on the rule spec and object hierarchies described in Scoping Constraints.
  

  Object or Constraint Group	Primary Constraint Group(s)
  group2group	InterChild constraint group
  route	Default constraint group on the route
  Term, InstTerm	Taper constraint group on the Term or InstTerm
  net	Default constraint group on the net, also inputTaper, outputTaper, or shield constraint group as appropriate
  net group	Default, reflexive, or transreflexive constraint group on the net group
  default	Global net default route spec
  design	Design route spec of the design database
  foundry	Foundry route spec in the Open Access technology database

• Category
  Identifies the constraint category based on the constraint’s function.
• Group Operator
  Specifies whether the constraint can be assigned to an AND or OR constraint group.
• OpenAccess API
  For OpenAccess built-in constraints, the OpenAccess constraint definition is given, otherwise custom.

Related Topics

Constraints Summary

Constraint Definitions

Constraint Group Types

Return to top