Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [qucs]

Quite Universal Circuit Simulator (QUCS) is an open source analog and digital circuit simulator package.

Qucs which stands for Quite Universal Circuit Simulator is an open source circuit simulator package released under the GPL license. From the Qucs project page where downloads are available for Windows, Ubuntu and OS X the project description is:

Qucs is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window.

  • The software aims to support all kinds of circuit simulation types, e.g. DC, AC, S-parameter, Harmonic Balance analysis, noise analysis, etc.

  • Qucsator, the simulation backend, is a command line circuit simulator. It takes a network list in a certain format as input and outputs a Qucs dataset. It has been programmed for usage in the Qucs project but may also be used by other applications.

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Qucs model for 2.4 GHz matching circuit

I am designing a matching circuit for an EFR32BG13 SoC. The current board layout looks like this: In addition to the visible layers (top and bottom), layer 2 is a solid ground plane and layer 3 is a solid VCC plane. As a bit of a learning…
Michael Cooper
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Nonlinear equation solvers in SPICE simulators

We have an assignment at the Parallel processing class, the target is to implement a Non-linear Equations solver on cuda based on Newton Raphson method and to interface this solver with an application that deals with nonlinear set of equations. We…
Elbehery
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Qucs - what is DC sweep?

I'm learning how to use Qucs using the tutorial. But I have no idea what is DC sweep, AC sweep, parameter sweep, Vsweep, ... and so why to even use them. Could anyone please help explain what are these "sweep" terms? P.S. I'm not an electrical…
Toussaint
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How do I import a spice model into QUCS

I am trying to import one of the spice models (from here) into QUCS. I haven't been able to find much documentation about this except for vague hints that it is possible.
user2557313
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Qucs simulation of quarter wave microstrip stub doesn't match ideal calculaton

I'm trying to simulate the resonant frequency and insertion loss of a 3 mm open stub on a 10 mm microstrip transmission line (50 Ω) on a FR-4 PCB (εr = 4.0, height = 0.1 mm). I calculated that the microstrip width should be around 0.188…
比尔盖子
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How do I measure the characteristics of a voltage divider in a QUCS simulation?

How do I measure the characteristics of a voltage divider in QUCS? Below is what I have tried thus far, using Qucs 0.0.15 on Ubuntu 10.04 I want to measure how the voltage at the center of a voltage divider changes based on R2 in the schematic…
JonnyRo
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How can I create a new component using Qucs?

I'm using Qucs for a simulation, but I don't understand how can I create a new component (E.g. a new LED from a data sheet). How can create it and use it easily in my project?
G M
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Why is this point giving me 8.3 V?

I am trying to find the voltage at V2 using the wire label in the Qucs-s simulator, powered by Ngspice. I have used Ohm’s law (V=IR) to work out the the voltage across R1 which was 1.66 volts;, but the simulator is claiming that there is around…
Ekene Nwokedi
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Is there a way to open/import gschem .sch file in qucs?

Is there a way to open .sch files produced by gschem in qucs? The two applications use different file formats. Does anyone know if a converter exists?
fukanchik
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Coupled Line Filter Design in Qucs

I'm getting to grips with designing coupled line filters and wanted to implement the band-pass filter described in Example 8.7, p. 435 in David Pozar's excellent "Microwave Engineering" just as a first toe-dip into the discipline. However, the…
electroGeek
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QucsStudio: Unknown variable

I'm using QucsStudio4.3.1 to simulate a voltage divider circuit. Everything is fine until I try to plot the result. The tutorial shown like below But the result I got is like Missing a properties from a "battery"(V1.I) Even I tried to manually…
Jack Huang
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How do I find the -3dB point on a given graph

I just performed an AC Simulation on QUCS and was asked to find values of gain and phase at low freq. and high freq and at the -3dB frequency point with the roll-off slope. The circuit is an RC circuit as shown below (image was taken from QUCS…
gann
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Non-inverting UA741 opamp simulation on QUCS

According with instructions provided here https://www.youtube.com/watch?v=dBY1k5qK2w4 (in Spanish), I tried to simulate an inverting opamp configuration, but I couldn't figure out the right vout behavior, as reported in the second graph of the…
Stefano Fedele
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Simulate capacitor discharge in Qucs

I want to find how long a capacitor takes to discharge from 12 volts to 2 volts using Qucs. I can use a voltmeter to measure the voltage across it when it charges up, but I cannot turn the power source off during simulation. Suggestions? Thanks
Corey
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QUCS simulation of simple capacitor/resistor circuit - strange results.

Hi I have just started to learn electronics. In order to understand the RC constant I have built the following very simple circuit in QUCS simulator. According to the formula RC time constant = R x C = 2,000,000 ohms x 0.000015 farads = 30…
Boris
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