Qucs-S is a circuit simulation program based on Qucs circuit simulator. The "S" letter indicates SPICE. The purpose of the Qucs-S project is to use free SPICE circuit simulation kernels with the GUI based on Qt toolkit. It merges the power of SPICE and the simplicity of the Qucs GUI. Qucs-S is not a simulator by itself, but it requires to use an external simulation backend with it. Qucs-S allows to use the following open-source simulation kernels:
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 and for RF and microwave circuits design.
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Recent Releases
24.4.129 Nov 2024 19:25
minor bugfix:
:
Improved diagrams rendering speed #1042.
hardcoded version in LC Cauer filter #1039.
pulsed current source show exit status if Ngspice crashes #1001.
Localization:
Russian translation update #1038.
Packaging:
Prepare for Flatpak package #51.
24.4.028 Nov 2024 09:45
major bugfix:
New features:
Implemnted touchstone (S2P) files viewer tool #936.
VC resistor made available for SPICE and ADMS-independent #959.
Library update:
Added SPICE_Tline library containing transmission lines for Ngspice #896.
:
Don't resolve paths to relaive if document is not saved and not belong to project #951.
Allow variables for potentiometer and diode device properties #1021 #1013.
simulation properties editing #968.
disbale simulation for XYCE #965.
running simulation in CLI mode #962.
memory leaks #960.
BJTsub and diode devices #983.
Schottky diode symbol appearence #1027.
crash if no simulator found on the first start #979.
artifacts when selecting elliptic arc #987.
text rendiering for Qt6.8.0 #1002.
QucsatorRF:
QucsatorRF updated to v1.0.3. See the release notes.
24.3.225 Nov 2024 04:25
minor bugfix:
:
Editing of File-type properties #948.
Implemented @model param syntax recognition for Parameter sweep #948.
24.3.123 Nov 2024 07:25
minor bugfix:
Packaging:
Stable release packages are now generated autmatically using Github CI #871.
and general improvements:
Improved temperature sweep using unified devices #925.
library manger always substitute absoute path #923.
stars/circles/arrows plots rendering #892.
library devices symbol text rendering #873.
touchstones files export from GUI #910.
mathicng circuit tool Implemented SPICE entry for DC block and DC feed #889.
Octave start #883.
right scroll wires selection decimal separators processing in attenuator tool #864.
Libraries:
Update Optocoupler.lib #846.
Localization:
Updated Russian translation #885.
24.3.031 Jul 2024 02:25
major feature:
New features:
SpiceLibComp redesign. This device is renamed to *Spice Library Device and provides an easy way
to add SPICE model to schematic and assign symbol to it. See #679.
Added possibity to import SPICE model for Diode, BJT, MOSFET, and JFET unified devices (blue) #795.
Implemeted symbol files (`*.sym`) editing mode. These files are needed to attach symbol to SPICE devices #700.
Redesign of schematic rendering engine. Improve rendering quality on HiDPI displays #723.
Improved Qucsconv GUI to reflect new converter features #826.
Improved libraries portability, relative path support for libraries, show libraries from project directory #567.
QucsatorRF updated to version 1.0.1.
Deprecated features:
The `*.qucs` binary archives are not supported anymore. Use system archivers to pack the projects instead #811.
The `SweepModel` property of *Parameter Sweep simulaiton has been deprecated. It is not needed anymore after Ngspice
has added variable sweep feature. Use variable sweep instead #839.
Packaging:
Introduced continous release of Linux, Windows, and Mac packages #719.
Added MacOS package build #797.
General improvements:
The TEMP and TEMPER variables are recognized by parameter sweep to apply temperature sweep #816.
ASCO optimization with QucsatorRF #830.
Enabled variables as parameters for unified nonlinear devices and pulsed source #838 and #808.
with XYCE simulation #701.
Improved attenuator synthesis tool #722.
Improved filter synthesis tool #715 #673.
Redesign *File- Open examples menu. Show open dialog instead of file manager #672.
Qucs-S now follows XDG standard for cached data location #145.
Apply.OPTION INTERP when simulating transient with parameter sweep; prevent broken par. sweep data #766.
Component library:
Added new Varactor library #759.
Added new PIN diode library #764.
Localization:
Russian translation update.
24.2.131 Mar 2024 16:25
minor bugfix:
This release contains no new features except the ing of the critical.
General improvements:
Zero output on DC bias simulation (F8) #667.
Build failure of the Fedora RPM becuase of RPATH in qucsator_rf.
24.2.026 Mar 2024 11:05
major bugfix:
New features:
QucsatorRF is now a part of the package; No need to compile and install qucsator manually #370.
Qucs-RFLayout tool could be launched from *Tools menu #465; this tool must be installed separated.
Redesign of the Qucsconv GUI #647.
Matching tool backported from Qucs-0.0.20 #401.
Added *RF devices group; backported different RF devices for Qucsator #607.
General imporvements and :
parameter sweep step @ivandi69.
SPICE devices bounding box #590 #637.
netlist export from CLI #639.
parameter sweep simulation with Xyce #624.
Revert explicit WITH_QT6 compile flag because of cmake tuner for German locale #416.
Refactoring in schematic editor #626 #618 @wawuwo.
Localization:
Russian translation update.
24.1.018 Feb 2024 13:35
major feature:
Important notes
Versioning switched to CalVer. The first digit means year, the second digit means the release number,
the third digit means patch number #328
Qucs-S is now on Telegram. Join https://t.me/qucs_s to ask questions and get news
New features
Added 3-pin RCD devices #349 to improve support of microelectronics PDKs
Improvements of Ngspice support; allowed multiple simulation of the same type #463 by @ivandi69
Automatic extraction of THD from FOURIER simulation #525 @ivandi69
Nutmeg equations improvements; implemented simulation selection from drop-down list #463 #519
Improvements of Nutmeg script simulation type; implemented custom prefixes for plots #476 #435 @ivandi69
Export DC OP simulation data to dataset #463 #140 @ivandi69
Implemented zoom by selection on the rectangular plots #305
Implemeted potentiometer device #122
Switched digital simulation from FreeHDL to GHDL #395 @iwbnwif
Status bar improvements #493
RF simulation features
Added RCLG device support for SPICE #564
Added YLIN device support for XYCE #451
Fixed touchstone simulation issues for Ngspice #392
Added BiasT device support for SPICE #374
Added option to disable transient model for RF port #410
Libraries
Fixed different issues related to creating libraries #432
Added audio IC library
Added loudspeaker library #421
Added comparators library #436
Modified voltage regulators library #433
Added voltage references library #439
Added thermistor library #538
Fixed ideal library #258 #428
Fixed transformers library #362
Added new devices in SpiceOpamp library #501
General improvements
Fixed different tuner issues
Schematic zooming improvements #502
Different improvements on schematic look and control
Added schematic pan mode with the middle mouse button #488
Many HiDPI support improvements including grid rendering
Fixed schematic glitches using Wayland
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