EMC and EMI
Return Path
Purpose: Reduce electromagnetic interference by checking that signals are following a proper return path.
OrCAD X Constraints support return path checking for Impedance and EMI.
Steps to implement return path checks:
1. Open the constraint manager.
2. Go to the worksheet found in Electrical > Electrical Constraint Set > Routing > Return Path.
3. Right-click on the DSN cell name (P3449_B01…), create an Electrical CSet, give it a name, and then it will add itself to
your list of ECSets (see below).
4. Whether you create an ECSet or use an existing one, you have multiple options available for return path checks.
5. You can set the right reference Nets and layers for your signals.
6. After such, to apply the rules, go to Electrical > Net > Routing > Return Path, choose the net to which you want to
apply your ECSet, and that's it.
8 www.cadence.com
OrCAD X Constraint Management Guide
