Running Simulations

The SIwave platform includes multiple solvers. Each solver offers a different combination of uses along three dimensions: the scale of features that can be conveniently solved, the applicability of the solution to signal integrity or power integrity issues, and the degree of integration into SIwave.

Solver Scale

Solvers fall into three classes when you consider the scale of geometric features that can be solved conveniently.

Small-scale solvers can solve selected traces, signals, nets and ICs.
Medium-scale solvers can handle packages and packages with ICs.
Large-scale solvers can analyze PCBs, with or without Packages and ICs.

Solver Applicability

A solver can yield results for signal integrity or power integrity studies (including thermal).

Degree of Integration into SIwave

Solvers can be accessible from within SIwave as tools, as solvers on demand, or as cosimulators using dynamic links. Some are external cosimulators, which use the import and export functions.

S-Parameter Tools are accessed from the Tools menu (See: Network Data Explorer and SUtility).
Solvers on Demand and Cosimulators using dynamic links are accessible from the Simulation menu.
Import and Export operations are accessed from the File menu, from simulation setup menus, and from simulation results menus.

Summary Table for SIwave Solvers

Table 1 summarizes the scale, integration, and applicability of the SIwave solvers, with links.

Solver	Description
SIwave SYZ	The SIwave SYZ extractor is a high-speed hybrid solver for medium and large-scale analysis of PCBs and packages. SIwave SYZ calculates frequency-dependent S-parameters for signal integrity and EMI investigations, as well as board-level power supply impedance modeling. The SIwave SYZ solver is accessed via the Simulation menu.
SIwave Resonant Modes	On-demand Resonant mode analysis solves for frequency-dependent voltage swings between layers of a PCB or multi-layer package. The SIwave Resonant Mode solver is accessed via the Simulation menu.
SIwave DC_IR	DC_IR analysis solves for the voltage drop across the power plane of the PCB. The DC solution can provide you with important information pertaining to power delivery. The SIwave DC_IR solver is accessed via the Simulation menu.
SIwave EM MTTF	The EM MTTF simulation provides an estimate of Mean Time to Failure (MTTF) of metallization due to electron flow, based on Black's Equation.
SIwave Frequency Sweep	Frequency sweep analysis allows you to evaluate the effects on the voltage and current distribution of applied AC voltage and current sources on your PCB across a specified frequency range. The SIwave Frequency Sweep solver is accessed via the Simulation menu.
SIwave Near Fields	The SIwave Near Field solver analyzes the radiated fields associated with a PCB. The near-field region exists at less than a wavelength from an energy source. Near fields can play a role in EMI. The SIwave Near Field solver is accessed via the Simulation menu.
SIwave Far Fields	The SIwave Near Field solver analyzes the radiated fields associated with a PCB. The far-field radiation occurs at more than a wavelength from an energy source. Far-fields can play a role in EMI. The SIwave Far Field solver is accessed via the Simulation menu.
SIwave Induced Voltage	SIwave Induced Voltage solver computes the induced voltage generated on the board by a plane wave incident at a particular angle and having a specific polarization.
PSI SYZ	PSI extracts the SYZ-parameters with high-speed Finite Element Meshing (FEM) using prism elements. PSI SYZ is optimized for power integrity and signal integrity analyses of packages. The PSI SYZ solver is accessed via the Simulation menu.
PSI AC Currents	The PSI AC Current solver evaluates the effects on the voltage and current distribution of applied AC voltage and current sources on a package across a specified frequency range. The PSI AC Current solver is accessed via the Simulation menu.
HFSS 3D Layout SYZ	The HFSS 3D Layout SYZ solver handles signal integrity analyses of layer-based ECAD designs with 3D precision. HFSS 3D Layout analyses typically focus on individual traces or nets within a package or PCB. The HFSS 3D Layout SYZ solver is accessed via the Simulation menu.
PI Advisor	The SIwave PI Advisor performs a loop inductance and sensitivity analysis on the capacitors already mounted on the PCB. The analysis produces several solutions or schemes, each of which seeks to optimize the trade-off between cost and performance. PI Advisor is accessed from the Simulation menu.
SIwizard	You can initiate a cosimulation with Ansys Electronics Desktop Circuit/Schematic from SIwave. By default, the SIwizard uses the Ansys Electronics Desktop-SIwave dynamic link. Selected nets are given ports and buffer models and set up as S-parameter dynamic link N-ports in Ansys Electronics Desktop. SIwizard is accessed from the Simulation menu.
TDRwizard	You can initiate a cosimulation with Ansys Electronics Desktop Circuit/Schematic from SIwave. By default, the TDRwizard uses a Nexxim netlist that points to a S-parameter touchstone file generated from SIwave. You can also use a schematic approach that has a Ansys Electronics Desktop-SIwave dynamic link. The TDRwizard automates the creation of pin groups for power/ground pins and of ports on both signal and power nets.
PDN Channel Builder	PDN Channel Builder extracts a power delivery network (PDN) model in either SIwave or PSI. It generates a power channel model of a combined die and package. The model includes the Power and Ground nets in the die and the voltage regulator module (VRM). PDN Channel Builder is accessed from the Simulation menu.
IC Die Network	If your design contains a set of pins representing connection points for an IC die, you can create an IC Die Network. Such a network consists of resistive and/or capacitive elements that model the on-chip power distribution (e.g., VDD and GND net) interconnect parasitics. Create IC Die Network is accessed from the Tools menu.
Signal Net Analyzer	The Signal Net Analyzer gives you the ability to get a quick idea of characteristic impedance and also to rapidly generate transient voltage waveforms of pin-to-pin signal propagation by co-simulating with HSPICE or Nexxim. Traces comprising propagation path are modeled as frequency dependent W-element transmission lines and source/sink pins can have IBIS driver/receiver models. Signal Net Analyzer is accessed from the Tools menu.
Capacitor/Inductor Library Browser	The Capacitor/Inductor Library Browser allows you to define VRM parameters and impedance requirements for a PCB, then automatically select and mount capacitors that meet the impedance requirements. You can plot the impedance of vendor or imported capacitor components versus frequency. The Capacitor/Inductor Library Browser is accessed from the Tools menu.
Q3D SYZ	The Q3D SYZ solver provides 3D accuracy for package-level SI analyses. The interface to Q3D is via 3D export.
HFSS for MCAD SYZ	The HFSS for MCAD SYZ solver produces high accuracy for critical traces. The interface to HFSS for MCAD is via 3D export.
RedHawk, Totem	The Apache tools are optimized power analyses of packages and ICs. The interface to these tools is via CPM import, and SSO export.
Icepak	Ansys Icepak performs thermal analysis of PCB-level designs. The interface to Icepak is via file import and export from the DC_IR solver.
CPA	A CPA model comprises DC resistance and low frequency inductance and capacitance effects. High resolution resistance and inductance color maps generated after running a CPA simulation help in package probing. A comprehensive HTML reporting feature summarizes the layout geometry, setup and simulation results. The CPA model can be seamlessly imported into Ansys RedHawk for Chip + Package cosimulation.

Simulation Options and Setup

Before starting simulation, some preliminary steps are typically required (e.g., you may need to identify power and ground nets and define ports or voltage probes). See Simulation Setup for details.

SIwave, PSI, HFSS 3D Layout, and Q3D Extractor have options that you can set as part of the Simulation menu.