Why to Use Allegro System Capture – Creating Differential Pairs

A differential pair represents a pair of Xnets or nets, which are routed differentially. That is, two complementary signals are transmitted over two traces to minimize the noise and EMI.

In System Capture, you can create differential pairs in multiple ways.

To create a differential pair, select the two signals on the schematic canvas, right-click and choose Assign Differential Pairs. Assign a differential pair name and click OK.

Select the net and check its constraints to see the differential pair assignment.

You can also use the Tools > Auto Create Differential Pairs option to create differential pairs automatically. The naming convention for nets that form a differential pair follow a predefined pattern that can be configured in the CDS_SITE area.

System Capture also supports automatic creation of differential pairs using a Tcl command. Refer to our earlier post for details.

Team DesignTech
Cadence Design Systems