Ansys SIwave is a comprehensive PI/SI/EMI electromagnetic analysis tool. It is the right environment for any PCB or package designer, and it is also very useful for RF engineers to analyze, design, and optimize power planes, RF interconnects, and mitigate EMI issues.
SIwave is one application but includes multiple solvers, each dedicated to a specific task.
SIwave Solvers
| Solver | Description | Purpose |
|---|---|---|
| Validation Check | Physical integrity check of nets | Analysis |
| EMI Scanner | Examines traces, planes, and components against EMI best practices | Analysis |
| DCIR | DC analysis of planes and traces | Analysis |
| EM MTTF | Median Time to Failure estimation, based on DCIR results | Reliability |
| SYZ | AC EM solver for S-parameters and Z-parameters | Analysis |
| Resonant Modes | Derives resonant modes of power planes | Debugging |
| Frequency Sweep | Similar to SYZ but excites ports with voltage/current | Analysis |
| Far Field | Computes radiated EMI | Analysis |
| Near Field | Computes near fields for debugging radiation sources | Debugging |
| Induced Voltage | Computes induced voltage on ports when exposed to external fields | Analysis |
| Signal Net Analyzer | Inspects trace geometry and electrical characteristics | Analysis |
| Impedance Scanner | Extracts impedance of RF lines | Analysis |
| Crosstalk Scanner | Identifies weak or high-coupling regions in RF lines | Debugging |
| SI Wizard | Automates SI analysis for RF traces | Analysis |
| DDR Wizard | Automates SI analysis for DDR interfaces | Analysis |
| TDR Wizard | Performs TDR on RF lines for debugging | Debugging |
| RLCG | Derives R, L, C, G parameters of traces/planes | Analysis |
| AC Current | Computes voltage/current distribution vs frequency | Analysis |
| SYZ PSI | Equivalent to SYZ, tailored for PDN analysis | Analysis |
| PI Advisor | Optimizes decap count and values | Optimization |
| Icepak | Thermal analysis based on DCIR solution | Analysis |
Excitations and Requirements
To run any solver, specific excitations must be defined. SIwave supports:
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RF ports (single-ended, differential, connector)
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Voltage sources
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Current sources/sinks
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Voltage probes
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Terminations
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Circuit inputs (from AEDT Circuit for co-simulation)
The workflow is straightforward:
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Select the excitation type.
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Pick two points in the layout.
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SIwave automatically detects the nets across all layers.
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Assign the connection by selecting the proper layers.
Excitation Requirements per Solver
| Solver | Port/Source Type | Manual Assign | Wizard Assign | Circuit Input |
|---|---|---|---|---|
| DCIR | Voltage/Current | ✔ | DCIR Wizard | – |
| PI / SYZ | Port | ✔ | PI Wizard | – |
| Resonant Modes | None | – | – | – |
| Frequency Sweep | Voltage/Current | ✔ | DCIR Wizard | ✔ |
| Far Field | Voltage/Current | ✔ | DCIR Wizard | ✔ |
| Near Field | Voltage/Current | ✔ | DCIR Wizard | ✔ |
| Induced Voltage | Port | ✔ | PI Wizard | – |
| Signal Net Analyzer | None | – | – | – |
| Impedance Scan | None | – | – | – |
| Crosstalk Scan | None | – | – | – |
| SI Wizard | Port | – | SI Wizard | – |
| DDR Wizard | Port | – | DDR Wizard | – |
| TDR Wizard | TDR Probe | – | TDR Wizard | – |
| RLCG | Source/Sink | ✔ | PI Wizard | – |
| RLCG / CPA | Source/Sink | ✔ | PI Wizard | – |
| AC Current | Voltage/Current | ✔ | DCIR Wizard | – |
| SYZ Parameters | Port | ✔ | PI Wizard | – |
| PI Advisor | Port | ✔ | PI Wizard | – |
| Icepak / MTTF | – | – | From DCIR | – |
Summary
SIwave is not a single solver but a platform of specialized EM solvers under one environment.
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It allows signal integrity (SI) engineers to analyze traces, DDR, SerDes, and RF interconnects.
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It provides power integrity (PI) engineers with PDN impedance, ripple current, IR drop, and decap optimization.
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It enables EMI engineers to predict both near-field and far-field radiation.
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With thermal coupling (Icepak) and reliability checks (MTTF), it covers end-to-end PCB/package multiphysics.
