endOfLineKeepout

In some processes, the spacing from the end of a line to other shapes on the same layer is specified by a simple keep-out region around the end of the line. Depending on the process, if a corner of another shape or a corner or an edge intersect the keep-out area, it may cause a violation. However, in some processes, if the corner or edge that intersects the keep-out area is part of the same metal shape, it is not considered as a violation. This rule applies to wires where ends of lines are less than a given width.

endOfLineKeepout Quick Reference

Constraint Type	Layer (non-symmetric)
Value Types	`ValueArrayValue`
Database Types	Design, Technology
Scope	design, foundry
Category	Spacing
Group Operators	AND, OR

Value Type

ValueArrayValue

Specifies that the value array should contain the following three values in the following order:

backwardExt defines the part of the keep-out area that extends back from the end-of-line edge
sideExt defines the lateral dimensions of the keep-out area that extend from the sides of the end-of-line edge
forwardExt specifies the keep-out region that is forward from the end-of-line edge

Required Parameters

width

Specifies that the constraint applies for all lines with eolWidth less than the value of width.

Type: Value

Optional Parameters

`cornerOnly`	Specifies that only a corner is considered as a violation. If this parameter is not present or is set to `false` (the default), it is considered a violation if either an edge or a corner of another shape intersects the keep-out region. Type: `BoolValue`
`exceptConnectivityType`
	When set to 2 (contiguousShapesConnectivityType), the constraint does not apply to the edges and corners of the same metal shape. If this parameter is not specified, the constraint applies to all shapes. Type: `StringAsIntValue` 0 anyConnectivityType 1 sameNetConnectivityType 2 contiguousShapesConnectivityType 3 directShapesConnectivityType 4 sameViaConnectivityType
`maxParallelRunLength`
	Specifies that the constraint applies if the parallel run length between the end-of-line shape and the other shape is less than this value. (Also supports negative parallel run length.) Type: `Value`
`exceptFrom`	Specifies that the rule applies only if the neighbor wire is not coming from either the front edge (when set to 1) or the back edge (when set to 2) of the keepout region. Type: `IntValue` 1 exceptFromFrontEdge 2 exceptFromBackEdge
`twoSides`	Specifies that the rule applies only if the shape under consideration has different mask wires on either side. Type: `BoolValue`
`colorMask`	Specifies that the constraint applies only to trigger wires on the specified mask Type: `IntValue` 0 any 1 mask1 2 mask2 3 mask3

Examples

set_constraint_parameter -name width -Value 0.2
set_constraint_parameter -name cornerOnly -BoolValue false
set_layer_constraint -group foundry -layer Metal2 \
  -constraint endOfLineKeepout -hardness hard -ValueArrayValue (0.3 0.5 0.1)

Specifies a simple keep-out region around the end of the line under the following conditions:

All lines have the end-of-line width less than 0.2
cornerOnly is set to false
Constraint applies to all shapes.

Virtuoso Space-based Router Constraint Reference
Product Version IC23.1, June 2023