Calculating Impedance Using the Layer Stackup Wizard (HFSS 3D Layout)

From the Trace Computation Settings area of the Layer Stackup Wizard, you can configure and perform an impedance calculation.

Prerequisites:

• Use the View Pane to select a layer. The Selected Layer Name field displays the currently selected layer.
• Click Trace Cross Section to open the Trace Cross Section editor.
• Click the Frequency drop-down menu to select the frequency.

To calculate impedance:

1. Select the Analysis tab.
2. Select the Single Ended Nets tab.
3. Select your reference layers.
   Note:

   Top and bottom reference layer must be selected in order to use multi-layer features of W-element export.

4. From the Trace Width field, enter a trace width.
5. If you wish to define coplanar waveguide reference planes, select Define CPW ref. planes (edge-to-edge) to enable additional options.
   • You may select Left plane spacing, Right plane spacing, or both.
   • For W-element export, selecting Left plane spacing means that aggressors may only be added to the right of a victim trace; any traces to the left are removed. Selecting Right plane spacing means that aggressors may only be added to the left of a victim trace; any traces to the right are removed.
6. Click Compute Z0.
7. The Z0 field updates to show the result.



8. To apply this setting to one layer or all layers, click Apply or Apply to all.