Questions tagged [circuitlab]
CircuitLab is a browser-based schematic and circuit simulation application.
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Output of op-amp in Multisim and CircuitLab
I have two identical circuits of op-amp one in MultiSim and one in CircuitLab. They show different current out of the op-amp and I am not sure why.
Here is the MultiSim circuit.
In case it is not ...
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3
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Help "Non-finite value" Circuit Lab Error
After running DC Simulation in CircuitLab, I get this error message:
"Error building graph: non-finite value."
What is going on? I'm new at this, so anything could be wrong. First, to ...
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Common base configuration
I have tried to implement this circuit of common base configuration but the power supply used in the lab is very confusing and I suspect it’s the reason why my readings aren’t turning out right (it’s ...
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Is CircuitLab's coupled inductor code broken?
I was working on an answer for this question, using CircuitLab but getting inexplicable results. The circuit oscillated, but the voltages were off. I was using CircuitLab's coupled inductor feature ...
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3
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BJT Differential Amplifier problem
I have tried to reproduce and understand the BJT differential amplifier, and unfourtunetely I have encountered some issues. The circuit is from Art of Electronics, 3rd edition.
First, my question is ...
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Proper way to model solar panel using CircuitLab
I'm trying to simulate a very simple (primitive?) circuit to charge a battery from a solar cell.
The solar cell was scavenged from a long string of lights. With a 50 Ω resistor it produces about 6.6 ...
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Is there a minimum voltage for digital logic (eg XOR) in CircuitLab?
I am trying to design an edge to glitch converter (XOR time delay) that works at 3 V.
For context: This is to wake an ESP8266 when a sensor value changes. I am fairly certain at this point that the ...
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Why does the 2N7000 in CircuitLab not behave the same as on my breadboard?
When simulating the 2N7000 in CircuitLab, I was surprised to see that the current was lower than expected for my circuit (90mA at the drain) when the gate is at 3.3 V. So, I built a quick breadboard ...
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How to simulate series capacitors in CircuitLab?
I am reading through the book Practical Electronics for Inventors, specifically the section on capacitors. I read that capacitors in series will an have equivalent capacitance C with formula
$$
C=(1/...
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Circuitlab - How can I create my own transistor model?
I would like to create some transistors, like the S8050 transistor, for to use in CircuitLab.
What I found is https://www.circuitlab.com/docs/custom-device-models/
If I open another existing ...
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CircuitLab DC parameter sweep problem circuit
The following circuit, taken from this answer seems to give odd results when doing a parameter sweep simulation on CircuitLab. Is the problem with CircuitLab, or is there some problem with the circuit ...
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Simulation Error in Circuit Lab with 2 Dependent Sources
simulate this circuit – Schematic created using CircuitLab
I'm practicing some problems and came across this circuit. It asks for the Thevenin equivalent with respect to terminals A and B. I ...
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1
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279
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Why is CircuitLab so slow to simulate this simple circuit? (Op Amp DC-coupled to BJT phase splitter.)
Not sure how much is known or published about the back end of CircuitLab, but:
While simulating a different circuit, I noticed very long simulation time. I narrowed the culprit down to the below ...
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Plot Z vs frequency for RLC circuit in CircuitLab
I am trying to simulate the resonance frequency of an antenna that can be modeled by a resistor in series with an inductor, both in parallel with a capacitor:
By attaching the antenna to an AC ...
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How can I set the maximum current in my CircuitLab circuit?
I have designed a circuit for two electromagnets to be turned on and off by a Raspberry Pi, but the total current draw by the circuit is 10.99A and my power pack has a limit of 2A. How can I simulate ...
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1
answer
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Difficulty using CircuitLab to build a Zener Diode Voltage Regulator Circuit
So I'm trying to build a Zener Diode Voltage Regulator in CircuitLab.
I've been searching around Google for some insight into building these, however, I'm required to use a triangle wave input, ...
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CircuitLab with fixed frequency
Inspired by this SE question, I was wondering how good CircuitLab would be a solving this type of problem.
Why do we not include the current source when finding the Thévenin equivalent impedance?...
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2
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379
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How do I do calculation in CircuitLab? How do I provide +Vcc and -Vcc to the OpAmp?
Here is my simple circuit. I would like to test whether the output is correct as per manual calculation. According to manual calculation, Gain=3.1, Vo=10.54V.
My question are:
How do I do that ...
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CircuitLab simulation of 555 timer - OUT HIGH always delivering 5V irrespective of Vcc?
I've scratched together a design for a 555 timer based driver for an IR540 MOSFET. But in CircuitLab the simulator shows the 555's OUT voltage is always 5V when high, for Vcc ranges 3.3V through 24V. ...
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How to achieve mutual inductance and CM choke simulation in CircuitLab?
This site is using CircuitLab. In some SPICE programs it is possible to simulate CM choke. For example:
Mutual Inductance is designated in a SPICE netlist by beginning the
first word (label) of a ...
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Modeling impedance matching network
Background
I'm looking at the RF (LNA_IN) pin of ESP32 as described in esp32_hardware_design_guidelines.
According to this document, the output impedance of the RF pins of ESP32 are (30+j10) or (35+...
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Simulating the discharge of a condenser using CircuitLab
Intro:
While studying for a Signals and Systems exams for tomorrow i decided to simulate an exercise and prove my answers are right.
simulate this circuit – Schematic created using CircuitLab
...
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How can I add variable duty cycle PWM to a CircuitLab simulation within a question?
This is my first attempt to simulate a circuit in the time domain with CircuitLab. In order to ask a proper question about something similar driven with PWM, I'd like to add an adjustable duty cycle ...
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Battery charging circuit
Can anyone assist me with correcting this circuit?
I'm trying to build a 12 V lead acid battery charger that would have a green LED indicator when charging and a red LED indicator when fully charged. ...
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2
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How do I use Circuit Lab to show me Voltage and current information on this circuit?
I have a bunch of red LEDs, I don't have their data sheet and I am trying to figure out a safe resistor to use to lower the current across them safely.
My current setup is as follows:
simulate this ...
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Voltage Clipping with Two Series-Opposing Zener Diodes
Theory
Schematic for Voltage Clipping with Two Series-Opposing / Bidirectional Zener Diodes
Consider the following schematic for voltage clipping with two series-opposing/bidirectional Zener Diodes \...
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4
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Single-supply op-amp behavior with 0V input
I am confused by how op-amps work. I have a single-supply op-amp: the power rails are +5V and ground. The circuit in the image says the op-amp is an LM741 but it's actually the op-amp built into the ...
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PhotoMOS simulation circuit
I want to simulate the following PhotoMos in CircuitLab for switching circuit but i didn't find the model for any photomos in CircuitLab. I was preparing a simulation for a switching MOSFET circuit ...
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CircuitLab voltage source question
I was having a problem with one of my circuits in CircuitLab, and traced it down to my sources always enabled, even if I switch them off by connecting to an open switch. This seems to be so simple, ...
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