Issue link: https://resources.pcb.cadence.com/i/1532920
Layer restrictions Purpose: Control EMI by limiting the layers through which a trace can be routed. For example, keep high-speed signals on internal layers sandwiched between ground planes for better shielding. Example: 1. Open the Constraint Manager. 2. Go to the worksheet Electrical Constraint Set > Routing > Wiring. 3. Create an electrical constraint set and give it a name (e.g. ECS1) shown below. 4. Click the cell under the Layer Sets column that is in the same row as your ECS1 row. The Select Layer Sets window pulls up. 5. We don't have any layer sets defined, so click the Define LayerSets… button. 6. Enter a name for the Layer Set: HS_TOP_INNER, then hit New. That creates the layer set. 7. Next, depending on your application, choose which layers you want this rule to apply to. For example, we would prefer high-speed signals to be routed on the top of the PCB and the inner layer and in some cases the GND layer, but no traces are allowed on the bottom half of the PCB (to control for Capacitive plane couple, controlling the EM signals in the Z-axis, etc.). 8. Click OK. Then you're taken back to the Select Layer Sets window. 20 www.cadence.com OrCAD X Constraint Management Guide