Where To Find This Example
AWR Version 14
AWR Version 13
Multi-Layer Parameterized Via
This example shows a multilayer PCB design with a via going through multiple ground layers. The goal is to design the layer transition such that there would be as little reflection as possible.
Simulating this project is time-consuming. This example, with the datasets included, is available at: http://kb.awr.com/display/Examples/Multi_Layer_Parameterized_Via
The “Top” schematic is setup to use the “Parameterized_Via” EM structure as a subcircuit. The EM structure is a multi-layer PCB with a via surrounded by an opening. The radius for the opening is passed into the schematic which can then be varied or tuned. Parameter interpolation is enabled for the EM structure which allows the user to select values in-between values that were simulated. After the EM simulation is complete, you can use the tuner and tune through the radius of the opening and watch the return loss vary.
Parameterized Via EM Structure
The via spacing is created by using Layer Boolean shape modifiers where one shape is subtracted from another. The radius of the via spacing is also modified using Circle Radius shape modifiers. Using the shape modifiers in this way allow the user to maintain the size and position of the via while simultaneously varying the radius of the spacing for every layer. Shape modifiers are layout objects that can manipulate shapes in various ways so that users parameterize their own geometries.
The radius of the via spacing is controlled by a variable and a sweep variable block in the EM schematic. This is the variable that is passed up and set in the Top schematic. . Also you can right click on the EM structure and select Preview Geometry to inspect the geometries for the different sweeps.
S11 of both the EM Structure and the schematic are plotted. Each value of the sweep for the EM Structure is plotted while the schematic is showing an interpolated point in-between the discrete sweep values that were simulated.