Questions tagged [simulation]
About tools to simulate circuits. Specify the tool used.
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What are the freeware SPICE simulators available?
Does anyone know of a freeware SPICE / circuit simulator?
SPICE (Simulation Program with Integrated Circuit Emphasis) is a general-purpose, open source analog electronic circuit simulator. It is a ...
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LTspice automation
I have a battery-powered boost converter and I'm attempting to measure the maximum input (battery) voltage droop under various load conditions of high current draws (different duty-cycles/...
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Simulating a variable mutual inductance model
Can we simulate a time varying mutual inductance in Matlab Simulink (or any other simulation tool).
Matlab Simulink has a variable inductor, but I could not find not mutual inductor.
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LTspice: Vary a resistor's value over time
I want to simulate the load regulation of a power-supply. I'm sure I remember being able to vary the value of a resistor over the course of a simulation in LTspice, but I can't remember how. Anyone?
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LTSpice capacitance dependend on voltage source
I am looking for a way to change the value of a capacitance dependent on the voltage source of the circuit.
How do I create a voltage dependent capacitor in LT spice?
Edit:
Two capacitances in a row ...
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How determinate parameters for thermal-model battery (Advanced question about battery modelling)
I'm trying to simulate an electrical model based on Ceraolo battery model for lead-acid battery. The challenge in this model is to determine the parameters that describe it.
I can understand and ...
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How do Circuit Simulators actually work?
I recently had the opportunity to play around with LiveWire, which is a circuit simulator and began wondering how exactly they computed the voltages across each component and the current going through ...
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Modeling a solar panel for simulations
I need to simulate a power conversion system (using SIMetrix/SIMPLIS) in which solar energy is captured by a solar panel, which is then connected to an inverter for supplying current to the grid. ...
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What exactly are IBIS simulation models? Can I use them like a normal simulation component?
I read a lot about IBIS. "What I understood is that they basically model the input and output voltage and current data based on actual performance instead of describing them through equations ...
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How to trace down why LTSpice simulation is slow?
I have a pretty complicated schematic in LTSpice (at least it is the most complicated schematic I ever tried to simulate in LTSpice).
For some reason simulation of just 20 ms turns into about 15 ...
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How to create Spice / LTSpice repeatable damped sinusoid
Is there a more elegant and/or simpler method to model a repeating, damped sinusoid from SPICE or LTSpice rather than chaining the damped SINE sources in series? Below is a schematic and the ...
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Diode Bridge in Simulator not behaving as expected
Hi I have a Diode Bridge as outlined in the image below. As you can see I am getting a negative voltage on one pair of diodes instead of this voltage being flipped to positive.
Can you see anything ...
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How does this BJT affect the circuit? If it does, how should I simulate on Circuitlab to see the effect?
I am trying to understand how NPN Q23 in the picture below affects the operation of the left circuit.
If it doesn't then what we get is the circuit on the right with the only transistor now being Q30....
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Can't simulate RC in LTspice
I am trying to learn LTspice. I have drawn a simple RC circuit and the probe-cursor is currently at the node connecting the cap and the resistor (Vc) (cursor image is not captured by PrintScreen).
I ...
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How do I learn HDL
I have a course in Digital Design in this semester and just love it. Now I know that most of the work in embedded system and digital design is done on computer simulators first and then implemented ...
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How to change the top directory in LTspice?
I installed LTspice in C:\Program Files, and when I go to "search components", the top directory is C:\Documents.
How can I ...
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How do I achieve XY mode on LTspice?
I have two node voltages that I wish to plot against each other, similar to the XY mode on an oscilloscope. How do I achieve this via LTspice? LTspice only plots quantities against time.
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LTspice error: timestep too small
This is the error I see:
This is my simulation command:
What is the issue here?
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KCL vs KVL in circuit analysis
I'm making a simplified version of SPICE to teach basic electronics to high school students (This is for a high school independent study).
Why does SPICE analyze circuits using Kirchhoff's current ...
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How can I use/model a custom diode in LTSpice?
I would like to simulate the behaviour of a zener diode in LTspice. Consider the following schematic
simulate this circuit – Schematic created using CircuitLab
I'm interested in simulating its ...
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How to make LTSpice sub-circuits available globally?
LTSpice Hierachy block can not be found if it is not in current working directory.
I am using this tutorial to create sub-circuits in LTSpice:
http://www.audio-perfection.com/spice-ltspice/...
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How to plot voltage vs current graph on Proteus Software?
I have designed a basic Series Regulator which implements fold back current limiting. I wish to simulate this on Proteus software.
I am expecting the following graph which shows how the output ...
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References for writing spice model code?
I'm currently looking into building my own spice models from datasheet specs to ensure accuracy. Are there any references for this sort of thing? I've looked around online and haven't found anything ...
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How to take Time Measurements using LT Spice
I've been fooling around with LT spice .MEAS feature for a while now and I just can't seem to determine how to take the time measurements I need for an assignment.
I can look at the time values on ...
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LTSpice Simulation - How to design a non ideal voltage source and limit its current?
I am trying to simulate a circuit which should pull the supply down.
The problem here is that the supply is not current limited and the whole voltage is dropping across the \$0.1\Omega\$ RC of Q4 and ...
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LTSpice: Find settling time using .meas
I want to find the settling time (i.e. the voltage at C1 not leaving a band of 1% anymore) of a step response in a circuit like this:
The step response looks like ...
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LTspice simulation doesn't work, what am I doing wrong?
We were talking about this simple ramp generator: What would be the simplest BJT based *linear* ramp generator?
and talking about simulation. So I downloaded LTspice drew up the circuit and started to ...
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How to approximate the behavior of a phototransistor in the circuit editor?
While phototransistors are often used in this common turbidity sensor application (at least in part) because of their gain, their response is not linear since the gain will depend on the intensity of ...
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What is the fool-proof method to confirm whether the op-amp has -ve feedback?
As the theory goes, following are the 2 cases of op-amp operation:
If there is a valid -ve feedback, inverting terminal volt = non inverting terminal voltage
If there is no -ve feedback, o/p acts ...
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which is the best circuit simulator for my purpose?
hi all i want to know the the limit of my circuit,upto which it can withstand,so that i can select or change the components accordingly.When i tried simulation in NI MltiSIM, it works fine,but the ...
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How to explain the strange results from this circuit (op-amp : differential amplifier?)
I have a differential amplifier. Problem of "gain" of the op-amp or "how it is wired."
I have simulated this as a voltage source controlled voltage (VofV.)
As a generic amplifer.
...
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Is it possible to model a PIN InGasAS photodiode in a SPICE simulator?
I want to know if it is possible to model a InGasAs panchromatic PIN photodiode, in accord with datasheet, in simulator SPICE MicroCAP 12. Because the supplier doesn't provide a SPICE model. And if it ...
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LTSpice Transient Analysis - How to specify the number of data points per step
I performed a 1us duration transient analysis on a basic inverting op-amp circuit with the resistor value Rx sweeping from 846 Ohms to 1385 Ohms. When I export the data to a text file (File -> Export ...
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Simulation of a class E power oscillator using LTspice
My goal is to understand and design a class E power oscillator. To this end, I am trying simulate the following schematic using LTSpice. Circuit topology and the design values are extracted from the ...
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Can anyone tell me how to find permittivity of a dielectric sample using a rectangular waveguide
Im trying to find the material paramters of a dielectric sample using a waveguide(X band) employing the Transmission/Reflection technique. While performing simulation in CST, how to properly orient ...
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Keysight's Advanced Design System users, what's wrong with this common drain circuit simulation?
For those of you that use Advanced Design System (ADS), from this circuit:
Fundamental Frequency for transient simulation tool is set to 1 GHz.
Yet, I'm getting this output:
Main question:
Since ...
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Investigating the effect of PCB layout parasitic in an op-amp amplifier by simulation
Would you please let me know what components I should add to my schematic as result of PCB parasitic to make my simulation more accurate?
As an example, the following image shows an amplifier ...
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Free online circuit simulator [closed]
Is there some free online circuit simulator where I can see see the electrons fluxing,imitating real-life circuitry?
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What's wrong with my RC circuit transient simulation in Cadence Virtuoso?
I am trying to do a simple RC transient simulation in Cadence virtuoso. Please see the circuit below:
I am trying to see the transient current and voltage of the capacitor being charged,however I got ...
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Free circuit simulator for educational purposes
I am looking for a free circuit simulator for educational purposes. My requirements are:
Visual ("draw a circuit diagram, click simulate")
It should contain light bulbs as circuit components such ...
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Comparison Between SPICE Simulators
I've recently realized that I can't do everything easily in ngspice, mainly because analysis has to be performed through the interpreter. I'm considering switching to a new SPICE simulator.
I'd like ...
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What do HDLs compile/synthesize to?
I'm a software engineer. As a programmer, I have an understanding of what my compiler does for me because I've manually written a close textual representation of what it outputs (e.g. assembly). For ...
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Simple Circuit Simulation tutorial
For the last few days I have been trying without any luck to find a good tutorial on simple circuit simulations. I am a relatively new hobbyist and I figure if I use simulations and play around the ...
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How to plot current in ngspice?
I wish to plot out the current and power in ngspice. In the case of voltage, for example, if I wanted to plot the voltage at node 1 I would use:
plot v(1)
...
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Does an ideal capacitor dissipate power?
On several circuit simulators I have seen capacitors with a "Power" figure.
Also, I have wondered how capacitive power supplies work.
Does an ideal, zero resistance, zero leakage, zero inductance ...
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Program for simulating circuits on linux [closed]
Do you know any program that works on linux and can simulate complex circuits?
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Fastest way to get integer mod 10 and integer divide 10?
If a hardware doesn't support modulus or division operations, it takes many more CPU cycles to simulate modulus/division by software. Is there any faster way to calculate division and modulus if the ...
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LTspice: How can I show multiple probes with waveforms using stepping parameters in different colors?
I'm using LTspice IV (4.23I) and I am using the .step command to vary the capacitance of a capacitor, so that I can see multiple waveforms for a single probe.
If ...
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Can you interface a Modelsim testbench with an external stimuli
I am working on a team that is doing both driver software and FPGA development. The FPGA simulation is being done in Modelsim and driver software is written in C. To minimize integration risk, I ...
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