oaMinEdgeAdjacentLength

Sets the minimum length for edges on a polygon that are adjacent to an edge that is shorter than a specified length. Some processes require specific length values for both adjacent edges. For other processes, the constraint applies if a convex corner lies between two concave corners and if the length of one of the edges which form the convex corner is shorter than a specified length, then the length of the other convex corner edge must be greater than or equal to the value of the constraint.

oaMinEdgeAdjacentLength Quick Reference

Value Types

oaMinEdgeAdjacentLength constraints have the following value types:

• Value
  Specifies the minimum length, in user units, of edges adjacent to the short edge when convexCorner is false or not given. When convexCorner is true, this specifies the minimum length, in user units, of the longer convex corner edge.
  

  Format	Example
  Tcl	set_constraint_parameter -name maxLength -Value f_maxLength set_layer_constraint -constraint oaMinEdgeAdjacentLength \ -layer s_layer \  -Value f_length
  LEF	LAYER s_layer PROPERTY LEF58_MINSTEP "MINSTEP f_maxLength MINADJACENTLENGTH f_length ;" ;
  Virtuoso	spacings( ( minEdgeAdjacentLength s_layer 'maxLength f_maxLength f_length ) )

• DualValue
  Specifies the minimum lengths, in user units, for the two edges adjacent to the short edge.
  

  Format	Example
  Tcl	set_constraint_parameter -name maxLength -Value f_maxLength set_layer_constraint -constraint oaMinEdgeAdjacentLength \ -layer s_layer \  -DualValue {f_length1 f_length2}
  Virtuoso	spacings( ( minEdgeAdjacentLength s_layer 'maxLength f_maxLength ( f_length1 f_length2 ) ) )

Parameters

• convexCorner (BoolValue, optional) specifies whether the constraint applies when a convex corner lies between two concave corners. When true, if the length of one of the edges which form the convex corner is shorter than maxLength, then the length of the other convex corner edge must be greater than or equal to the value of the constraint. This parameter applies only when the constraint value type is Value.
• maxLength (Value, required) specifies that the constraint applies when the short edge is shorter than this value, in user units.
• concaveCorner (BoolValue, optional) specifies that if a concave corner is between two convex corners, and if the length of one of the edges that form the concave corner is less than maxLength, then the other length must be greater than or equal to the value of this constraint. The concaveCorner parameter is mutually exclusive with the convexCorner parameter.
  
  

Examples

Example 1—oaMinEdgeAdjacentLength with adjacent length minimums

• On Metal1, the length of edges adjacent to an edge shorter than 1.5 must be greater than or equal to 3.0.
• On Metal2, the length of one edge adjacent to an edge shorter than 1.5 must be greater than or equal to 2.0 and the length of a second edge adjacent to the edge shorter than 1.5 must be greater than or equal to 3.0.
  

  Format	Example
  Tcl	set_constraint_parameter -name maxLength -Value 1.5 set_layer_constraint -constraint oaMinEdgeAdjacentLength \ -layer Metal1 -Value 3.0 set_constraint_parameter -name maxLength -Value 1.5 set_layer_constraint -constraint oaMinEdgeAdjacentLength \ -layer Metal2 -DualValue {2.0 3.0}
  LEF	LAYER Metal1 PROPERTY LEF58_MINSTEP "MINSTEP 1.5 MINADJACENTLENGTH 3.0 ;" ;
  Virtuoso	spacings( ( minEdgeAdjacentLength Metal1 'maxLength 1.5 3.0) ( minEdgeAdjacentLength Metal2 'maxLength 1.5 (2.0 3.0) ) ) ; spacings

  

Example 2—oaMinEdgeAdjacentLength with convexCorner

The following example specifies that if a convex corner is between two concave corners, and one edge of the convex corner is less than 0.6 user units, then the other convex corner edge must be longer than or equal to 1.0 user units.

set_constraint_parameter -name maxLength -Value 0.6 
set_constraint_parameter -name convexCorner -BoolValue true 
set_layer_constraint -constraint oaMinEdgeAdjacentLength  \ 
 -layer Metal1 -Value 1.0 

LAYER Metal1 
 PROPERTY LEF58_MINSTEP
   "MINSTEP 0.6 MINADJACENTLENGTH 1.0  CONVEXCORNER ;" ;

spacings(
  ( minEdgeAdjacentLength Metal1 'maxLength 0.6 'edgeCount 1 'convexCorner 1.0 )
) ;spacings

Related Topics

Length and Width Constraints