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Execution of Simulations
2022.01.26
Points of this article
・To execute a simulation in the ROHM Solution Simulator, after starting up a Solution Circuit, click the Run button (?) on the circuit diagram toolbar.
・Upon clicking the Simulation Settings icon, simulation settings can be changed.
・Simulation results can be displayed as signal waveforms at different nodes using the Waveform Viewer tool.
The method of execution of simulations in the ROHM Solution Simulator is here explained. Those persons who have not read any introductory articles prior to this one should consult “Starting a Simulation Circuit in the ROHM Solution Simulator” to start up the example simulation circuit. The following link can also be used to start the simulation directly. https://www.rohm.com/solution-simulator/buck_converter_vo250v_io20a
For a quick introduction to methods of operation, please refer to the “Hands-On User’s Manual(PDF)”.
Execution of Simulations in the ROHM Solution Simulator
When the simulation circuit starts, a simulation screen is displayed, as in Fig. 1. To execute the simulation, click the Run button (▶) on the circuit diagram toolbar.
Fig.1. Execution of simulation in the ROHM Solution Simulator

When the simulation begins, the Run button (▶) changes to a red square (■) like that in Fig. 2. Moreover, a small window opens, and the type of simulation being executed (in Fig. 2, Time-Domain), the time for which the simulation is being executed (in Fig. 2, 2 ms), and the execution status are displayed. The simulation time (2 ms) is not the actual time required for the simulation, but the simulated time setting–meaning, for example, that the circuit action is to be simulated for a time interval of 2 ms starting from the time power is supplied.
Fig. 2. Display of the circuit diagram toolbar during simulation execution

When the simulation progress reaches 100%, the waveforms in the circuit diagram display area are updated. Upon clicking the red square button (■), the simulation is halted in mid-progress. However, it cannot be restarted.
Simulation settings can be changed by clicking on the Simulation Settings icon (Fig. 3). Simulation settings are set in advance according to the selected simulation circuit. The simulation type cannot be changed.
Fig. 3. Changing simulation settings using the Simulation Settings icon

Simulation results can be displayed as signal waveforms at different nodes using a Waveform Viewer tool. The display method is explained in the next article.
Learn Know-how
Electrical Circuit Design
- Soldering Techniques and Solder Types
- Seven Tools for Soldering
- Seven Techniques for Printed Circuit Board Reworking
-
Basic Alternating Current (AC)
- AC Circuits: Alternating Current, Waveforms, and Formulas
- Complex Numbers in AC Circuit
- Electrical Reactance
- What is Impedance? AC Circuit Analysis and Design
- Resonant Circuits: Resonant Frequency and Q Factor
- RLC Circuit: Series and Parallel, Applied circuits
- What is AC Power? Active Power, Reactive Power, Apparent Power
- Power Factor: Calculation and Efficiency Improvement
- What is PFC?
- Boundary Current Mode (BCM) PFC: Examples of Efficiency Improvement Using Diodes
- Continuous Current Mode (CCM) PFC: Examples of Efficiency Improvement Using Diode
- LED Illumination Circuits:Example of Efficiency Improvement and Noise Reduction Using MOSFETs
- PFC Circuits for Air Conditioners:Example of Efficiency Improvement Using MOSFETs and Diodes
-
Basic Direct Current (DC)
- Ohm’s Law: Voltage, Current, and Resistance
- Electric Current and Voltage in DC Circuits
- Kirchhoff’s Circuit Laws
- What Is Mesh Analysis (Mesh Current Method)?
- What Is Nodal Analysis (Nodal Voltage Analysis)?
- What Is Thevenin’s Theorem?: DC Circuit Analysis
- Norton’s Theorem: Equivalent Circuit Analysis
- What Is the Superposition Theorem?
- What Is the Δ–Y Transformation (Y–Δ Transformation)?
- Voltage Divider Circuit
- Current Divider and the Current Divider Rule
Thermal design
-
About Thermal Design
- Changes in Engineering Trends and Thermal Design
- A Mutual Understanding of Thermal Design
- Fundamentals of Thermal Resistance and Heat Dissipation: About Thermal Resistance
- Fundamentals of Thermal Resistance and Heat Dissipation: Heat Transmission and Heat Dissipation Paths
- Fundamentals of Thermal Resistance and Heat Dissipation : Thermal Resistance in Conduction
- Fundamentals of Thermal Resistance and Heat Dissipation : Thermal Resistance in Convection
- Fundamentals of Thermal Resistance and Heat Dissipation : Thermal Resistance in Emission
- Thermal Resistance Data: JEDEC Standards, Thermal Resistance Measurement Environments, and Circuit Boards
- Thermal Resistance Data: Actual Data Example
- Thermal Resistance Data: Definitions of Thermal Resistance, Thermal Characterization Parameters
- Thermal Resistance Data: θJA and ΨJT in Estimation of TJ: Part 1
- Thermal Resistance Data: θJA and ΨJT in Estimation of TJ: Part 2
- Surface Temperature Measurements: Methods for Fastening Thermocouples
- Surface Temperature Measurements: Thermocouple Mounting Position
- Surface Temperature Measurements: Treatment of Thermocouple Tips
- Surface Temperature Measurements: Influence of the Thermocouple
- Estimating TJ: Basic Calculation Equations
- Estimating TJ: Calculation Example Using θJA
- Estimating TJ: Calculation Example Using ΨJT
- Estimating TJ: Calculation Example Using Transient Thermal Resistance
- Estimation of Heat Dissipation Area in Surface Mounting and Points to be Noted
- Surface Temperature Measurements: Thermocouple Types
- Summary
- Collection of Important Points Relating to Thermal Design
Switching Noise
- Procedures in Noise Countermeasures
- What is EMC?
-
Dealing with Noise Using Capacitors
- Understanding the Frequency Characteristics of Capacitors, Relative to ESR and ESL
- Measures to Address Noise Using Capacitors
- Effective Use of Decoupling (Bypass) Capacitors Point 1
- Effective Use of Decoupling Capacitors Point 2
- Effective Use of Decoupling Capacitors, Other Matters to be Noted
- Effective Use of Decoupling Capacitors, Summary
-
Dealing with Noise Using Inductors
- Frequency-Impedance Characteristics of Inductors and Determination of Inductor’s Resonance Frequency
- Basic Characteristics of Ferrite Beads and Inductors and Noise Countermeasures Using Them
- Dealing with Noise Using Common Mode Filters
- Points to be Noted: Crosstalk and Noise from GND Lines
- Summary of Dealing with Noise Using Inductors
- Other Noise Countermeasures
- Basics of EMC – Summary
Simulation
- Thermal Simulation of PTC Heaters
- Thermal Simulation of Linear Regulators
-
Foundations of Electronic Circuit Simulation Introduction
- About SPICE
- SPICE Simulators and SPICE Models
- Types of SPICE simulation: DC Analysis, AC Analysis, Transient Analysis
- Types of SPICE simulation: Monte Carlo
- Convergence Properties and Stability of SPICE Simulations
- Types of SPICE Model
- SPICE Device Models: Diode Example–Part 1
- SPICE Device Models: Diode Example–Part 2
- SPICE Subcircuit Models: MOSFET Example―Part 1
- SPICE Subcircuit Models: MOSFET Example―Part 2
- SPICE Subcircuit Models: Models Using Mathematical Expressions
- About Thermal Models
- About Thermal Dynamic Model
- Summary
-
About the ROHM Solution Simulator
- How to Access the ROHM Solution Simulator
- Trying Out the ROHM Solution Simulator (1)
- Trying Out the ROHM Solution Simulator (2)
- Starting a Simulation Circuit in the ROHM Solution Simulator
- ROHM Solution Simulator Toolbar Functions and Basic Operations
- ROHM Solution Simulator: User Interface
- Execution of Simulations
- Method for Displaying Simulation Results
- Simulation Result Display Tool: Wavebox
- Simulation Results Display Tool: Waveform Viewer
- Customization of Simulations
- Exporting Circuit Data to PartQuest™ Explorer
- Purchasing Samples for Evaluation
- Optimization of PFC Circuits
- Optimization of Inverter Circuits
- About Thermal Simulations of DC-DC Converters