cutClassPreference

Specifies the cut class preferences to be used by the router. If the constraint does not exist, all vias by default are equally preferred. If the constraint exists, but a cut class or a set of cut classes does not exist in the list, those cut classes are less preferred than those in the list.

cutClassPreference Quick Reference

Constraint Type	Layer
Value Types	ValueArrayValue
Database Types	Design, Technology
Scope	design, foundry
Category	Via Construction
Group Operators	OR

Value Type

ValueArrayValue

Specifies a list of pairs of values that represent cut class dimensions. The values are specified in order of preference.

Required Parameters

None

Optional Parameters

None

Examples

create_constraint_group -name cutClassgp -opType or -db tech
add_constraint_group -subGroupName cutClassgp -groupType foundry

set_constraint_parameter -name className -StringValue Vx
set_constraint_parameter -name numCuts -IntValue 1
set_layer_constraint -constraint cutClass -layer Via1 -create true \
  -group cutClassgp -DualValue {0.5 0.5} 

set_constraint_parameter -name className -StringValue VxBar
set_constraint_parameter -name numCuts -IntValue 2 
set_layer_constraint -constraint cutClass -layer Via1 -create true \
  -group cutClassgp -DualValue {0.5 1.0} 

set_constraint_parameter -name className -StringValue VxLrg
set_constraint_parameter -name numCuts -IntValue 4 
set_layer_constraint -constraint cutClass -layer Via1 -create true \
  -group cutClassgp -DualValue {1.0 1.0} 

Creates the following three cut classes:

• Vx 0.5 0.5
• VxBar 0.5 1.0
• VxLrg 1.0 1.0

set_layer_constraint -constraint cutClassPreference -layer Via1 -create true \
  -group cutClassgp -ValueArrayValue {1.0 1.0}

Uses only VxLrg for routing.

set_layer_constraint -constraint cutClassPreference -layer Via1 -create true \
  -group cutClassgp -ValueArrayValue {1.0 1.0 0.5 1.0}

Causes VxLrg to be preferred over VxBar.

set_layer_constraint -constraint cutClassPreference -layer Via1 -create true \
  -group cutClassgp -ValueArrayValue {0.5 1.0 0.5 0.5}

Causes VxBar to be preferred over Vx.

Related Topics

Routing Constraints

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