Single-ended Impedance Control

Details on specifying and validating single-ended impedance-controlled nets, including supported impedances and calculation methods.

This constraint enables impedance-controlled routing for RF nets and other fast, long, or sensitive traces.

Automatic Detection

• Currently, single-ended impedance nets can only be entered manually.

Constraint details

Single-ended impedance control can be applied to nets in the "Single Ended Impedance Signals" section of Circuit Comprehension. You can add them one at a time, match them using regex, or apply a netclass.

To define a high current net constraint, you need to fill in the following fields:

1. Net name

2. Target impedance (we currently support 50Ω and 75Ω)

3. Signal frequency (GHz)

Quilter will automatically perform the impedance control calculations that take into account the specified stack-up's material properties to determine the correct trace width necessary to achieve the specified impedance within a tolerance of 5%.

Physics Rule Checks

The following PRCs validate this constraint after compilation:

Invalid Width Span determines the length of trace paths in a net are outside of an acceptable tolerance threshold. A trace segment has an “invalid width” if its width is outside of a 10% tolerance when compared to the nominal value.

Ground Plane Overlap determines if the ground plane below net traces overlaps at all relevant points.