The Open Source CAD System For Everyone

1. The program appears to be free for non-commercial use only (that is, although it uses Spice3 which is open source, the overall Mac port seems to have a more restrictive licence). 3.Qucs Qucs is a circuit simulator with graphical user interface. The software aims to support all kinds of circuit simulation types, e.g. DC, AC, S-parameter.
2. Between 2003, and January 2015, the sourceforge Qucs download statistics show that over one million downloads of the software have been recorded. As well as extensive circuit simulation capabilities Qucs supports a full range of.

QCAD is a free, open source application for computer aided drafting (CAD) in two dimensions (2D). With QCAD you can create technical drawings such as plans for buildings, interiors, mechanical parts or schematics and diagrams. QCAD works on Windows, macOS and Linux. The source code of QCAD is released under the GPL version 3 (GPLv3), a popular Open Source license.

Download the latest version of Qucs for Windows. Design and simulation of integrated electronic circuits. Qucs, also known as Quite Universal Circuit Simulator.

The current version of QCAD is 3.25.

QCAD was designed with modularity, extensibility and portability in mind. But what people notice most often about QCAD is its intuitive user interface. QCAD is an easy to use but powerful 2D CAD system for everyone. You don't need any CAD experience to get started with QCAD immediately. You can download QCAD today for free!

Main Features

• Layers
• Blocks (grouping)
• 35 CAD fonts included
• Support for TrueType fonts
• Various Metrical and Imperial units
• DXF and DWG input and output
• Printing to scale
• Printing on multiple pages
• Over 40 construction tools
• Over 20 modification tools
• Construction and modification of points, lines, arcs, circles, ellipses, splines, polylines, texts, dimensions, hatches, fills, raster images
• Various powerful entity selection tools
• Object snaps
• Measuring tools
• Part library with over 4800 CAD parts
• Very complete and extremely powerful ECMAScript (JavaScript) scripting interface
• Command line tools (dwg2pdf, dwg2svg, dwg2bmp, etc.)
• QCAD/CAM:

Click here for a complete list of features.

Qucs-S: Qucs with SPICE

Download links The latest stable release is Qucs-0.0.22. It is based on stable Qucs-0.0.19: Documentation at the readthedocs.io and here Source tarball: qucs-s-0.0.22.tar.gz AppImage for all Linux distributions at Github Debian repository (32 and 64 bit), built with openSUSE OBS: Debian 10 'Buster', Debian 9 'Stretch', Debian 8 'Jessy', Debian 7 'Wheezy' and Ubuntu 14.04 , 16.04 , and 18.04 RPM Packages (32 and 64 bit) for CentOS and Fedora-24, 25, and 26 Slackware>=14.1 SlackBuild Windows installer (Zipped EXE): qucs-s-0.0.22-setup.zip (Installation instructions...) Contibuition guide Qucs-S is open for everyone's contribution. See here for contribution guide.

News January, 19, 2020 Qucs-S-0.0.22 is released! See Release notes and dowload link October, 31, 2018 Qucs-S-0.0.21 is released! See Release notes and dowload link June, 24, 2018 Added packages for Ubuntu 18.04 October, 31, 2017 Qucs-S-0.0.20 is released! See Release notes and dowload link October, 25, 2017 Added packages for CentOS and Fedora January, 26, 2017 Qucs-S 0.0.19 is released! The first stable release. Release announcement November 8, 2016 Qucs-S RC8 released. Release notes and download link September 3, 2016 Qucs-S RC7 released. Release notes and download link May 15, 2016 Qucs-S RC6 released. Release notes and download link March 23, 2016 Qucs-S RC5 released. Release notes and download link January 31, 2016 Qucs-S RC4 released. Release notes and download link August 29, 2015 Qucs-S RC3 released. July 28, 2015 Qucs-S RC2 released. July 25, 2015 Qucs-S RC1 released.

Simulation example with Qucs-S and Ngspice (More screenshots...) Publications Qucs-S is also a research software. Check our publication list.

What is Qucs-S?

Qucs-S is a spin-off of the Qucscross-platform circuit simulator. 'S' letter indicates SPICE. The purpose of the Qucs-S subproject is to use free SPICE circuit simulation kernels with the Qucs GUI. It merges the power of SPICE and the simplicity of the Qucs GUI. Qucs intentionally uses its own SPICE incompatible simulation kernel Qucsator.It has advanced RF and AC domain simulation features, but most of the existing industrial SPICE models are incompatible with it. Qucs-S is not a simulator by itself, but it requires to use a simulation backendwith it. The schematic document format of Qucs and Qucs-S are fully compatible. Qucs-S allows to use the following simulation kernels with it:

• Ngspice is recommended to use. Ngspice is powerful mixed-level/mixed-signal circuit simulator. The most of industrial SPICE models are compatible with Ngspice. It has an excellent performance for time-domain simulation of switching circuits and powerful postprocessor.
• XYCE is a new SPICE-compatible circuit simulator written by Sandia from the scratch. It supports basic SPICE simulation types and has an advanced RF simulation features such as Harmonic balance simulation.
• SpiceOpus is developed by the Faculty of Electrical Engineering of the Ljubljana University. It based on the SPICE-3f5 code
• Qucsator as backward compatible

Screenshots

MOSFET power switch	JFET mixer
Single-ended tube amplifier	Hi-Fi bipolar transistor audio amplifier

Main features

• Backward compatible with Qucs by the component types and simulations
• Direct support of SPICE models from components datasheets. SPICE model could be added to schematic without any adaptation.
• Basic SPICE components: RCL, BJT, MOSFET, JFET, MESFET, switches;
• Advanced SPICE components: Equation-defined sources and RCLs, transmission lines;
• Direct support of SPICE Modelcards, SPICE sections (.IC, .NODESET);
• Parametric circuits (.PARAM) and SPICE postrprocessor (Nutmeg)
• Basic SPICE simulations: DC, AC, TRAN;
• Advanced SPICE simulation: DISTO, NOISE, SENS (added in 0.0.20), Spectrum analysis;
• Single-tone and Multitone Harmonic balance analysis with XYCE backend;
• Nutmeg script simulation: direct access to the SPICE code and construct your own simulation;
• XYCE script simulation type;
• XYCE digital devices library;
• XSPICE CodeModel synthesizer;
• User mathematical functions definitions with .FUNC (added in 0.0.20);

Installation

Linux

AppImage for all Linux distributions

You can run Qucs-S on all Linux platforms using AppImage without building it from source. AppImage already includes Qt4 librariesand you don't need to install them explicitly. Simple make AppImage executable and run it from console or your file manager. Pleasenote that AppImage doesn't include Ngspice and you need to install them using system package manager.

Debian repository

Debian(7,8, and 9) and Ubuntu(14.04 and 16.04) repositories are available for Qucs-S. Packages arebuilt with automatic Open Build Service (OBS) tool from OpenSUSE team. Go to downloadrepositoryYou need to perform the following steps to add this repository in system (forDebian 9). For othe distributions simple replace the URLs.

• Download GPG key:
  wget -c
  http://download.opensuse.org/repositories/home:/ra3xdh/Debian_9.0/Release.key
  
• Add the following line to /etc/apt/sources.list:
  deb http://download.opensuse.org/repositories/home:/ra3xdh/Debian_9.0/ ./
  
• Import key and update repos:
  apt-key add Release.key
  apt-get update
  
• Install Qucs-S
  apt-get install qucs-s
  

If you have problems with adding repository in your system you can download andinstall the *.deb package manually with dpkg:

dpkg -i qucs-s-0.0.19S_amd64.deb
You may need to install the following dependencies: lib4qt4-qt3support,ibqt4-svg, ngspice

RPM packages for CentOS and Fedora

You need to simple add reposotries using the yum package manager. Let's consider example for CentOS:

• First add repository

  yum-config-manager --add-repo http://download.opensuse.org/repositories/home:/ra3xdh/CentOS_7/
  yum-config-manager --enable ra3xdh
  

• Then check that repository is added
  

  yum repolist alll

• And finally install the qucs-s package
  yum install qucs-s

Building from source

If binary packages are not available for your distrubution, then you will need to build Qucs-S from source:

• Install all necessary dependencies: Qt, C++ compilers, etc.
• Install desired simulation backends: Ngspice, XYCE, SpiceOpus. You can use all these backends together or only one of them. Install basic Qucs (0.0.18 or newer) if Qucsator is needed.
• Download and unpack tarball
• Use CMake to compile. Autotools doesn't support this installation mode and will not work!
• Invoke make and make install

The complete command sequence to build Qucs-S is following:

tar xvfz qucs-s-0.0.21.tar.gz
cd qucs-s-0.0.21
mkdir builddir
cd builddir
cmake ..
make
make install

The last command make install should be executed from root user. It willinstall Qucs-S into default prefix /usr/local/. Use -DCMAKE_INSTALL_PREFIX=... to override the default locationNo additional configure options are needed now.

Slackware SlackBuild

Slack Build script is available for Slackware distribution. It will download andcompile Qucs-S automatically. You will obtain the binary Qucs-S package. Performthe following steps to install Qucs-S:

1. Clone this repository:
   git clone https://github.com/ra3xdh/QucsS.SlackBuild
   
2. Run SlackBuild as root:
   cd QucsS.S.SlackBuild
   ./qucs-S.SlackBuild
   
3. Install txz package with installpkg command

Windows

You need to use binary installer for Windows. You need to download and installNgspice and/or XYCE manually from official websites: http://ngspice.org/https://xyce.sandia.gov respectively.

Important note for Ngspice on Windows: Unpack Ngspice ZIP package strictly to theC:SPICE location. Otherwise XSPICE model will not work! If you are getting strange errors with Ngspice on Windows and cannot ot simulate even simple circuit, please check that Ngspice is installed strictly in C:SPICE . All Ngspice packages including offcial should be installed in a such way.

It's recommended special build of Ngspice-26 for WindowsNgspice26_QucsS.zip. Default Ngspice package also will work but it may have some limitation. CustomNgspice build solves the following issues:

Qucs Mac Download Mac

• Windows GUI of Ngspice is disabled. It allows Qucs-S to obtain logs from Ngspice.
• Added CMPP preprocessor and C headers set mandatory for development of CodeModel libraries. Default Ngspice build is shipped without it.

Usage

Linux

Run qucs-s from the the command line or launch Qucs-S icon in your desktopenvironment menu after the installation. You will need to select default simulationbackend at the first run. You can change it later in the application settings.

Windows

Launch Qucs-S in the system Start menu. You will also need to select defaultsimulator on the first application start. You will need to set default simulatorat the first run. Correct simulator paths setting is necessary for Windows.

Authors

• Vadim Kuznetsov ra3xdh@gmail.com
• Mike Brinson mbrin72043@yahoo.co.uk

Contribution guide

Steps to contribute

Source code of the Qucs-S is hosted at the Github in the following repository: https://github.com/ra3xdh/qucs_s. You need to clone this repository if you wish to contribute.

git clone -b current https://github.com/ra3xdh/qucs_s
cd qucs_s
git checkout -b your_feature
Use CMake to compile Qucs-S. After you make changes, prepare a pull request to Qucs-S repository.

Branching model

Currently there are two main branches in my home Qucs repository:

• master is release candidate for the next Qucs-S release. This branch provides side-by-side installation of Qucs and Qucs-S. Main application executable is named to qucs-s. Only CMake is supported.
• current is development branch. Use this branch to target patches. It uses traditional Qucs build system. There may exist some experimental branches forked form this branch. I merge current into master time to time.

Release tarball is obtained from master with some Bash script. I distribute only Qucs-GUI and some utilities with Qucs-S package.

My changes only concentrated on GUI side, and you need to rebuild GUI only to test Qucs-S. You may take Qucsator from usual Qucs installation.

Qucs Mac Download Windows 10

Build instruction (development branches)

For qucs-s-stable you need to set WITH_SPICE cmake key. Autotools will not work. Perform the following commnads to build all: git clone https://github.com/ra3xdh/qucs_s/
cd qucs_s
mkdir build
cd build
cmake .. -DCMAKE_INSTALL_PREFIX=/some_path
make

Then install and launch qucs-s executable.(to top...)

Documentation

• Main documentation page at readthedocs.io
• Presentation at the Spring MOS-AK 2016 at Lausanne
• Presentation at the Spring MOS-AK 2017 at Lausanne
• Presentation at the MIXDES2017 conference: Part 1 and Part 2

Qucs Mac Os X Download

Publications

Qucs-S is not a simple circuit simulator, but also a research software. Pleasecite our articles, if you are using Qucs-S in your research.

1. Brinson, M. E., and Kuznetsov, V. (2016) A new approach to compact semiconductor device modelling with Qucs Verilog-A analogue module synthesis. Int. J. Numer. Model., 29: 1070-1088. (BibTeX)
2. D. Tomaszewski, G. Głuszko, M. Brinson, V. Kuznetsov and W. Grabinski, 'FOSS as an efficient tool for extraction of MOSFET compact model parameters,' 2016 MIXDES - 23rd International Conference Mixed Design of Integrated Circuits and Systems, Lodz, 2016, pp. 68-73. (BibTeX)
3. M. Brinson and V. Kuznetsov, 'Qucs-0.0.19S: A new open-source circuit simulator and its application for hardware design,' 2016 International Siberian Conference on Control and Communications (SIBCON), Moscow, 2016, pp. 1-5. (BibTeX)
4. M. Brinson and V. Kuznetsov, 'Improvements in Qucs-S equation-defined modelling of semiconductor devices and IC's,' 2017 MIXDES - 24th International Conference 'Mixed Design of Integrated Circuits and Systems, Bydgoszcz, 2017, pp. 137-142. (BibTeX)
5. M. Brinson and V. Kuznetsov, 'Extended behavioural device modelling and circuit simulation with Qucs-S' International Journal of Electronics, 2017, pp.1 - 14 (BibTeX)