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Types of SPICE simulation: DC Analysis, AC Analysis, Transient Analysis
2018.10.25
Points of this article
・SPICE-based simulators are provided with functions for DC analysis, AC analysis, transient analysis, Monte Carlo analysis, S parameter and Fourier analysis, and noise analysis, among others.
・Nearly all simulator software packages are provided with functions for DC analysis, AC analysis, transient analysis, and Monte Carlo analysis.
Here we describe representative analytical functions and present a summary to indicate the capabilities of a SPICE-based simulator.
Types of SPICE Simulation
The representative functions of SPICE-based simulators are summarized below. The highlighted DC analysis, AC analysis, transient analysis, and Monte Carlo functions are well-known analysis functions that are included in nearly all simulator software packages. These four types of function are explained in some detail. In this article, we discuss DC analysis, AC analysis, and transient analysis.
| Analysis Method | Function/Characteristic |
|---|---|
| DC analysis | Analysis of static characteristics. (All DC characteristics of the data sheet) |
| AC analysis | Analysis of frequency characteristics. (Capacitance, gain-phase) |
| Transient analysis | Time response analysis. (Oscilloscope) |
| Monte Carlo | Simulations that reflect variation in circuit elements. *Variation must be described in the model. The description format differs with the software. |
| S-parameter | High-frequency characteristic analysis. |
| Fourier analysis | High-frequency analysis and signal distortion analysis. |
| Noise analysis | Noise analysis at measurement points. *If noise is not included in the model, noise does not occur. |
SPICE Simulations: DC Analysis, AC Analysis, Transient Analysis
These analyses are the most basic fundamentals of device and circuit analysis, and so perhaps need not be explained here, but examples are shown below.
DC analysis is analysis of static characteristics. In the above example, the change in ID with VDS for a MOSFET is simulated. In general, values stipulated on the data sheet of a transistor, IC, or other device will include DC characteristics and AC characteristics. DC analysis is capable of simulation of all the DC characteristics in the data sheet.
AC analysis mainly addresses characteristics relating to frequency. Representative quantities include analysis of the impedance as a function of frequency and of the gain-phase characteristic. The above example simulates the gain and phase characteristics versus frequency for a filter circuit.
Transient analysis is analysis of the time response. The above example shows the step response of a filter, but this method is also often used in evaluation of the load transient response of switching power supplies. Transient analysis typically involves using an oscilloscope to observe waveforms.
The various simulators are provided with diverse functions for performing these analyses, such as current/voltage sources, function generators (oscillators), and current or voltage measurement; measurement results can be plotted in graphs.
In the next article, we will explain the remaining analysis type, Monte Carlo analysis.
Learn Know-how
Electrical Circuit Design
- Soldering Techniques and Solder Types
- Seven Tools for Soldering
- Seven Techniques for Printed Circuit Board Reworking
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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
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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
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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?
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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
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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
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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
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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