Constraint Groups in a Layer-based Design Partition

When you create a layer-based design partition, two constraint groups dedicated to it are also created automatically. These constraint groups are applied according to the Edit Scope settings to enable the layer constraint while routing.

The following table shows these two constraint groups associated with a design partition. The Type 1 constraint group uses the same name as the design partition, and the Type 2 constraint group adds _res_ to its name denoting that it restricts valid vias based on the design partition definition.

Design Partition	Constraint Group Type	Constraint Group Name	Process Rules	Via Availability	Edit Scope
cle_p1	Type 1	dsn:cle_p1	Valid Layers	Keep all valid vias inherited from the parent constraint group.	Only Select Inside Partition
	Type 2	dsn:cle_res_p1	Valid Layers Valid Vias	Restrict valid vias by removing those outside the design partition definition from the parent constraint group.	Only Edit Inside Partition

When you open a layer-based design partition, the Layer Palette, the Default Wire Constraint Group, and the Default Via Constraint Group change according to the Edit Scope.

The Only Select Inside Partition option is enabled by default, and when this option is active, the CLE filter is available in the Layer Palette.

The CLE filter is selected by default and lets you see only those layers that are available in the current layer-based design partition. Even if you deselect this filter to show all layers, the layers outside the design partition definition cannot be selected. The Default Wire Constraint Group and the Default Via Constraint Group change to the Type 1 constraint group. When you create or modify a via for which the cut layer is outside the current design partition definition, a warning glyph is displayed. Sign off these edits in the assistant to retain them.

Enabling the Only Edit Inside Partition option enables the CLE filter in the Layer Palette and applies the Type 2 constraint group.

If you change the status of Edit Scope to Off, the CLE filter in the Layer Palette is disabled and hidden and you can see and use all layers. The Default Wire Constraint Group and the Default Via Constraint Group are reset. You must sign off all intentional edits that are outside the current design partition.

Based on the edit mode, the constraint groups are defined in the following way:

• Only Select Inside Partition: Sets the constraint group with the valid layer-purpose pair constraint mapped to the layer-purpose pair of the design partition but the valid vias constraint includes all the vias.
• Only Edit Inside Partition: Sets the constraint group with valid layer-purpose pair and valid via constraint mapped to layer-purpose pair and via of the current design partition only.

Related Topics

Layer-Based Design Partition Routing Video

Defining a Layer-Based Design Partition

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