Getting Started with SIMetrix/SIMPLIS Intro: A Beginner’s Guide

Getting Started with SIMetrix/SIMPLIS Intro: A Beginner’s GuideSIMetrix/SIMPLIS Intro is a compact, entry-level simulation environment that combines the analog circuit simulation strengths of SIMetrix with the switched-mode power supply (SMPS) and power-electronics-oriented behavioral simulator SIMPLIS. This guide walks you through installation, interface basics, building and simulating your first circuit, common workflows for analog and power-electronics design, troubleshooting tips, and learning resources to help you become productive quickly.

Why choose SIMetrix/SIMPLIS Intro?

• Easy transition from schematic to simulation — the combined environment lets you draw realistic schematics and run fast, accurate simulations without switching tools.
• SMPS-focused features — SIMPLIS delivers efficient switching simulation for converters, controllers, and magnetic components.
• Educational and hobby-friendly — the Intro edition provides a capable feature set for students and beginners without the complexity of high-end packages.

Installation and getting set up

1. System requirements
   • Windows ⁄₁₁ (64-bit) is typically required. Check the current system requirements on the vendor site for RAM/CPU recommendations.
2. Obtain the software
   • Download SIMetrix/SIMPLIS Intro from the official SIMetrix/SIMPLIS website or your university/vendor distribution. You may need to register for a license or use a trial key.
3. Install and activate
   • Run the installer, follow prompts, and enter the license/trial key when requested. If activation requires an online server, ensure your firewall allows the activation process.
4. Folder and permissions
   • Install to a location where you have read/write permission (avoid Program Files restrictions if you plan to run scripts or save example projects).
5. Start the program and verify the license info under the Help/About menu.

Interface overview

The SIMetrix/SIMPLIS Intro workspace blends schematic capture, waveform viewing, and text editors for models and netlists.

• Schematic editor — draw circuits using components from the component library. Place parts, wires, labels, and hierarchical blocks.
• Toolbar and palettes — quick access to common components (resistors, capacitors, inductors, voltage sources, switches, op-amps, MOSFETs, etc.).
• Simulation control — set up analysis types (transient, AC, DC sweep, parametric runs), simulation time, and tolerances.
• Waveform viewer — view simulation results, measure voltages/currents, add cursors, and export data (CSV).
• SPICE netlist/text editor — inspect and modify the underlying netlist or behavioral models.
• Help and examples — a library of demo circuits and application notes to learn from.

Building your first circuit: a simple RC transient

Step-by-step: create and simulate a simple resistor-capacitor (RC) charge/discharge transient.

1. New schematic
   • File → New → Schematic.
2. Place components
   • From the component palette place: a resistor (R1), a capacitor (C1), a DC voltage source (V1), and a switch (SW1) or a pulse voltage source to simulate switching.
3. Wire up
   • Connect V1 to R1, R1 to C1, and C1 to ground. If using a switch, place it between V1 and R1.
4. Set component values
   • R1 = 10 kΩ, C1 = 1 µF, V1 = 5 V. Double-click components to edit values.
5. Add ground
   • Place the ground symbol and connect it to the negative terminal of the source and capacitor. (No circuit will simulate without a reference node.)
6. Choose analysis type
   • Set a transient analysis: run for 10 ms with a time step appropriate for the circuit (e.g., max step 1 µs).
7. Run simulation
   • Click Run.
8. View waveforms
   • In the waveform viewer, plot the capacitor voltage node (Vc). Use cursors or add a measurement expression to read time constants (τ = R·C). For R = 10 kΩ and C = 1 µF, τ = 10 ms.

Tip: If you used a pulse source, you can observe charge and discharge cycles; if a switch, toggle during simulation or use a time-controlled switch.

Using SIMPLIS features for switching power electronics

SIMPLIS is optimized for switching converters and control loops. Typical workflows:

• Choose an appropriate power switch element (ideal or realistic MOSFET/IGBT models). SIMPLIS often includes behavioral models optimized for fast switching and robust convergence.
• Model magnetics using the built-in coupled inductor/transformer elements with winding definitions and core parameters.
• Use idealized switching elements and averaged-model equivalents when you need faster simulation for control loop design or parameter sweeps.
• For gate drive and control ICs, use the included behavioral blocks or import vendor models. Many manufacturers supply SIMPLIS-compatible models for controllers and regulators.
• Use the “event-driven” nature of SIMPLIS where switching events are handled efficiently — ideal for long transient runs of converters under varying loads.

Example: simulate a buck converter

• Components: input source, power switch (MOSFET), diode or synchronous MOSFET, inductor, output capacitor, load resistor, and a PWM controller block.
• Run transient to observe startup, load-step, and steady-state ripple. Use the waveform viewer to measure output voltage ripple, inductor current, and switching node waveforms.

Simulation setup tips and best practices

• Always place a ground reference. Many errors come from missing reference nodes.
• Start with ideal components for functional checks, then switch to detailed models for performance analysis (losses, thermal).
• For switching circuits, use suitable time steps. SIMPLIS handles events well, but make sure you resolve switching edges if you need accurate waveforms (use max time step or event-based settings).
• Use initial conditions sparingly; let circuits settle unless you need a specific start state.
• Save snapshots of schematics and waveforms frequently; use versioned filenames.
• Use parameterized parts and .param (or equivalent) to run parametric sweeps easily (e.g., sweep load resistance or inductance).
• If a simulation fails to converge, try: relaxing tolerances, using an initial operating point, simplifying the circuit, or replacing problematic components with idealized versions temporarily.

Debugging common problems

• “No nodes found” or floating node warnings — ensure ground is present and every net is connected as intended.
• Convergence errors — reduce simulation precision, increase tolerances, simplify small time constants, or add small series resistances to ideal sources.
• Unreasonable voltages/currents — check part values, orientation of polarized parts, and probe nodes.
• Long simulation times — use averaged models, increase max timestep, or simulate shorter time ranges for initial checks.

Analysis and measurement tools

• Cursor and marker tools — measure delta time, voltage levels, rise/fall times, and frequency.
• FFT and spectral analysis — analyze switching noise and harmonic content.
• Parametric sweep and Monte Carlo (if supported in your edition) — evaluate sensitivity to component variation.
• Export data — save waveform traces as CSV for external analysis or reporting.

Example learning projects (progressive)

1. RC time constant and frequency response of an RC low-pass filter.
2. Op-amp inverting and noninverting amplifier — DC operating point and transient step response.
3. Single-switch buck converter — start-up, steady state, and load step.
4. Synchronous rectifier and efficiency comparison with diode rectifier.
5. Closed-loop voltage regulator — design a compensator, simulate loop stability (Bode plots if available or time-domain perturbations).

Helpful resources

• Built-in example library and demo projects — open these to see working circuits and recommended simulation settings.
• Official manuals and application notes — vendor docs often contain cookbooks for SMPS topologies.
• Community forums and university course materials — many educators post lab exercises and models.
• Manufacturer SIMPLIS models — check power IC vendors for controller models compatible with SIMPLIS.

Final recommendations

• Begin with simple circuits and progressively add complexity.
• Use SIMetrix’s schematic clarity for analog designs and SIMPLIS’s event-driven engine for switching power simulations.
• Lean on provided examples and vendor models to shorten the learning curve.

Good luck — start with the RC example above, then move to a basic buck converter to see the combined strengths of SIMetrix and SIMPLIS in action.