ViaExpert – Via Modeling and Simulation

Impedance discontinuity in the signal path has a significant impact on signal integrity for high speed channel design. Among the many discontinuities, via discontinuity is the critical one which requires extra attention in channel design. Three-dimensional full-wave EM simulation is constantly used to analyze via discontinuity. Conventional 3D full-wave simulation approach suffers from various drawbacks including the complex model creation and the long simulation time. ViaExpert provides a fast and accurate way to simulate via structures for both pre-layout and post-layout scenarios. The built-in connector footprint database allows users to quickly assemble the model with connector footprint, breakout region trace, and a given stackup.

ViaExpert supports many features below

  • Optimized mesh function improves simulation speed and precision.
  • Fast 3D FEM solver offers better fidelity and quality.
  • Fast Hybrid solver offers better capacity and speed compared to other tools in market.
  • Multiple ways to create models or import Allegro brd.
  • Auto port generation simplifies EM analysis setup.
  • Support parametric and optimization sweep simulation.
  • 3D-View makes the model check easier.
  • Export to HFSS and CTS.
  • SnpExpert displays S-parameter and TDR.


Multiple Ways to Create Models
ViaExpert provides many ways to create models quickly

  • Import PCB from Allegro layout file
  • Import footprint from built-in connector database
  • Create model from built-in via array template
  • Create model by build-in diff via template
  • Use built-in templates(SMD/SMA/BGA/AC Decap/) to create models

Trace Creat/Edit
ViaExpert allows users to create/edit/delete differential pair traces easily.

  • Support Arbitrary Type and create/edit traces in batches.
  • Support back drill and front drill.

3D View
Allow more direct visual examination of the via model, users can check the 3D view by hiding airbox, ports, PEC and layers or stretch the Z-axis.

ViaExpert templates
Build-in many templates for users to create model quickly and conveniently. For now, there are three templates: SMD, SMA and AC Decap flow. All the templates support reuse and parametric sweep.

Allow parametric and optimization setting before simulation:

  • Parametric supports sweep by different parameters and calculate each result.
  • Parameters in ViaExpert still can be used after exporting to HFSS.
  • Optimization help users find the optimal result as settings.

Fast 3D EM Solver
In order to achieve both accuracy and performance, ViaExpert provides two solver technologies:

  • Fast 3D full-wave Finite Element Method (FEM) solver, which ensures high accuracy.
  • Hybrid solver, which greatly increases the speed of simulation, far faster than FEM 3D solver.

Both of the solvers are in conjunction with parallelization technology, they adopt distributed processing and multi-core processing too.

Result Post-Process
S-parameter generated from ViaExpert is displayed by SnpExpert. User can enjoy the features offered by SnpExpert to explore the S-parameter such as

  • Single-ended to differential conversion
  • S-parameter to TDR conversion
  • Built-in FEXT, NEXT, PSXT, ILD, ICN and ICR plots
  • Built-in compliance metrics such as IEEE 802.3ba and OIF CEI-25G/28G
  • Built-in passivity, causality, reciprocity, stability metrics and enforcements