Qucs-S Legacy Help : User Manual and Reference Material

Be advised that this legacy documentation branch is no longer actively maintained. It is retained for archival/reference purposes, but may not accurately reflect the current features of QUCS-S. For the most up-to-date documentation, see the latest version on ReadTheDocs <https://qucs-s-help.readthedocs.io/en/latest/>.

Authors Mike Brinson (mbrin72043@yahoo.co.uk) and Vadim Kusnetsov (ra3xdh@gmail.com)

Copyright 2015, 2016, 2017, 2018

Permission is granted to copy, distribute and/or modify this document under the terms of the

GNU Free Documentation License, Version 1.1 or any later version published by the Free

Software Foundation. A copy of the license is included in the section entitled “GNU Free

Documentation License”.

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Contents:

• Introduction
  • Background
  • Qucs-0.0.18 Structure
  • Qucs future capabilities
  • A first view of the extended spice4qucs device modelling and simulation features
• Basic Ngspice, Xyce and SPICE OPUS simulation
  • Introduction
  • Supported simulators
  • General simulation methods
  • Variable names
  • DC simulation
  • AC simulation
  • TRANsient simulation
  • Other forms of simulation
  • Spice4qucs circuit simulation components
  • More basic simulation examples
    • DC Example 1: Calculating circuit input resistance and power dissipation in a resistor.
    • DC Example 2: Variation of power dissipation with varying DC input voltage.
• Spice4qucs subcircuits, macromodels and device libraries
  • Spice4qucs Subcircuits: with and without parameters
  • Spice4qucs subcircuits without parameters
  • Spice4qucs subcircuits with parameters
  • A second more complex example of Spice4qucs subcircuits with parameters
  • Component and circuit libraries
  • Using manufacturers component data libraries
  • Usage of unmodified SPICE Libraries
  • SpiceLibComp device
  • Symbol pattern files format description
  • Usage of the whole SPICE library
  • Libraries blacklisting
• Device and component modelling with algebraic equations
  • The role of algebraic and numeric equations in circuit simulation
  • Qucs equations usage with ngspice and Xyce
  • Manipulating simulation data with algebraic measurement scripts
  • Qucs Equation-Defined Device (EDD) models
  • Qucs Frequency Equation-Defined Device (FEDD) models
  • Ngspice and Xyce translation/synthesis of EDD and FEDD models
• More advanced circuit simulation techniques.
  • Fourier simulation
  • Additional Ngspice, SPICE OPUS and Xyce Fourier simulation examples
  • Distortion simulation
  • Noise simulation
  • One and two parameter sweep controlled simulations
  • Qucs and SPICE simulation of device and circuit temperature properties
  • Spectrum analysis with Ngspice and Nutmeg scripting
• Ngspice, Xyce and SPICE OPUS post-simulation data processing with Qucs-S and Octave
  • Introduction to capabilities
  • Ngspice and SPICE OPUS output data post-processing
  • Ngspice, SPICE OPUS and XYCE data post-processing operators and functions
  • Xyce simulation output data post processing with the Xyce script component and SPICE .PRINT statements
  • Ngspice and Xyce H SPICE style .measurement output data processing
  • Qucs-S emulation of the Qucs PlotVs() function
  • Qucs-S output data processing with the Octave numerical analysis and visualization package
  • Introduction
  • Using Octave for numerical analysis and visualization of Qucs-S simulation output data
  • The structure and content of Octave xxxxxx.m script files
  • A second Octave xxxxxx.m script file
• Qucs and SPICE simulation models that work with Ngspice, Xyce and SPICE OPUS
  • Introduction
  • Spice4qucs component specifications and technical reference
    • Capacitor (C)
    • Inductor (L)
    • Resistor (R)
    • Independent AC Current Source (I)
    • Independent AC Voltage Source (V)
    • Independent DC Current Source (I)
    • Independent DC Voltage Source (V)
    • Linear Current Controlled Current Source (F)
    • Linear Current Controlled Voltage Source (H)
    • Linear Voltage Controlled Current Source (G)
    • Linear Voltage Controlled Voltage Source (E)
    • Probes
    • Qucs Netlist
    • Ngspice Netlist
    • Relay (Voltage controlled switch) (S)
    • Diode (D)
    • BJT npn (Qucs T, ngspice Q)
    • Ngspice diode (D)
    • Ngspice linear resistor (R)
    • Ngspice linear capacitor (C)
    • Ngspice linear inductor (L)
    • Ngspice mutual inductor (K)
    • Ngspice independent AC voltage source (V)
    • Ngspice non-linear dependent voltage and current sources (B)
      • B source example 1: Simulation of the DC characteristics of a diode modelled with a B source pwl function; diode series resistor set at 1e-3 Ohm
      • B source example 2: Simulation of the properties of a high power half-wave rectifier circuit with 0.5 Ohm load
  • Linear and non-linear transformer models
    • Two winding transformer model with in phase primary and secondary voltages and winding resistance
    • Two winding transformer model with out of phase primary and secondary voltages and winding resistance
    • Two winding transformer model with in phase primary and secondary voltages, winding resistance and fringing inductance
    • Two winding transformer model with in phase primary and secondary voltages, winding resistance and core saturation
    • Spice4qucs magnetic core library: symbols and B/H specifications
    • Two winding transformer model with in phase primary and secondary voltages, winding resistance and core saturation (using XSPICE models)
    • Three winding transformer model with winding resistance and core saturation effects (using XSPICE models): full-wave rectifier example
  • More complex circuit simulations that demonstrate the use of spice4qucs models
• Ngspice custom simulation technology
  • Introduction
  • Setting up single and multiple circuit simulations
  • Extracting circuit and device properties from ngspice simulations
  • Statistical circuit simulation including Monte-Carlo analysis
  • Building ngnutmeg scripts for circuit simulation control and data analysis
• XSPICE standard components and library
• XSPICE user written device models and library
• Introduction to mixed analogue/digital simulation
  • XSPICE basics
  • Mixed mode simulation with Ngspice
  • Mixed mode simulation with Xyce
  • Mixed mode simulation with SPICE OPUS
• Verilog-A compact semiconductor device modelling
  • The Qucs/ADMS Verilog-A “turn key” modelling system
  • The Qucs Verilog-A module synthesizer
  • Using Xyce for Verilog-A compact device modelling
• RF simulation with Ngspice, Xyce and SPICE OPUS
  • Introduction to capabilities
  • Small signal AC S-parameter simulation
  • Small signal AC two port network simulation/analysis
  • Single tone large signal AC Harmonic Balance simulation
  • Multi-tone Large signal AC HB simulation
  • The SPICE OPUS large signal AC steady state transient shooting method
  • Emulation of Qucs RFEDD components
  • RF device models
    • RF resistor models
    • Metal thin-film axial leaded resistors
    • Surface mount chip resistors
  • More example RF circuit simulations
• Qucs-S/Octave circuit simulation and device parameter extraction interface
• Measurements
• References
  • Introduction
  • Background references
  • Later Qucs/Qucs-S references

A “Technical Description” of the Qucs simulator and implemented device models are available online at http://qucs.sourceforge.net/tech/technical.html.

Qucs-S example schematics can be found in the Qucs-S V0.0.21 source code “examples” directory.

Qucs_S V0.0.21 build can be downloaded from https://ra3xdh.github.io/.

Indices and tables

• Index

• Search Page