minLargeViaArraySpacing

Specifies the minimum spacing required between cut arrays (arraySpacing). The constraint only applies to the spacing between cut arrays, not between cuts within an array (cutSpacing). This constraint is associated with a cut layer.

Multiple via array spacing values can be specified for a cut layer, based on different array sizes.

minLargeViaArraySpacing Quick Reference

Value Type

minLargeViaArraySpacing constraints have a OneDTblValue to represent the large via array spacing that is required for various cut array sizes. The table lookup key is the number of cuts in the shortest direction of the via array (numCuts in the diagram below) and the table value is the required minimum array spacing.

For example, the number of cuts in a square NxN array is N, rather than the total number of cuts in the array. If neighboring cut arrays have different sizes, the number of cuts in the wider array is used to determine the array-to-array spacing. A cut array can be truncated if it does not fit within a wire. In this event, the large via array-to-array spacing is still used in placing the truncated array

set_layer_constraint -constraint minLargeViaArraySpacing \
 -layer s_layer -OneDTblValue {{i_numCuts f_spacing}…}

ARRAYSPACING 
  CUTSPACING cutSpacing 
  {ARRAYCUTS i_numCuts SPACING f_spacing} ... ;

Parameters

• cutClass (DualValue, optional) The constraint applies only to the cut class of the given dimensions.
• parallelOverlap (BoolValue, optional) The constraint applies only when there is a parallel edge overlap > 0.
• intraArrayCutSpacing (IntValue, optional) If this parameter is specified then the cuts which are spaced by less than this value, are considered to be part of the same array.

Examples

• Example 1 — minLargeViaArraySpacing example
• Example 2 — minLargeViaArraySpacing example using intraArrayCutSpacing

Example 1 — minLargeViaArraySpacing example

This example sets the minimum large via array spacing on Via1 according to the values in the following table.

set_layer_constraint -constraint minLargeViaArraySpacing \
 -layer Via1 -OneDTblValue { 2 0.10 3 0.20 }

Example 2 — minLargeViaArraySpacing example using intraArrayCutSpacing

Related Topics

Via Construction Constraints