Using Differential Pairs in Allegro PCB Editor
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Differential Impedance in Constraint Manager
Advanced Constraints can be used to view the Differential Impedance in Constraint
Manager.
A predefined constraint called DIFF_IMPEDANCE_RULE can be set up and added to
any worksheet. The constraint is added to the Net > Routing > Impedance worksheet.
You can add this constraint to any worksheet, or even add a new worksheet. For more
information on customizing worksheets, refer to the Customizing Worksheets section in
Allegro Constraint Manager User Guide.
Note: This constraint will not DRC on the PCB Editor/SI canvas. It will only report
failures in Constraint Manager.
1. In the Electrical domain of Constraint Manager, right-click on the Net header in
the worksheet selector and select Customize Worksheet.
2. Right-click on the Routing > Impedance header and select Add Column.
