Questions tagged [circuit-analysis]
Circuit (Network) analysis is the process of finding the voltages across, and the currents through, every component in the network. Consider using in conjunction with tags for the particular analysis technique(s) in question: "nodal-analysis", "mesh-analysis", "superposition", etc.
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Equivalent electrical circuit changing and power balance calculation
I tried to change this circuit in 3 different ways, but the power balance is not the same. The least power balance that I got was ~ 50W more and we need to find the balance between 0 and 5W. Do not ...
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How to find current in capacitor from equations for voltage and current source? [closed]
How to find iA when t > 0?
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I have a basic LED circuit with an STM32F030R8T6 which is not working and I cannot figure out why
Apologies as this is a somewhat vague question but I cannot figure out what is wrong with my circuit/program and I have been stuck on this for a couple of weeks now.
I have this circuit I put together ...
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Single fault protection for battery management circuit
I am seeking design guidance for a circuit that has been significantly simplified to drive the point home.
I am looking for options to safely disconnect the battery to protect my circuit in the event ...
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Converting Balanced Audio to Unbalanced Audio without Damaging Sink
I want to receive a stereo balanced audio signal and feed it into the stereo microphone inputs via my motherboard's header pins.
I added about a 30 dB reduction in gain which looks good on the scope ...
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Input resistance of an inverter op-amp circuit
I need to find the input resistance of this circuit. There are two parts of this exercise:
The first one is to find the input resistance of the circuit without the capacitor.
The second is to the ...
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Is RC frequency response related to series RC or parallel RC?
So in playing around with some frequency response stuff I made this circuit:
And I found that the cutoff frequency value is set by the Feedback Resistor and the capacitor. Take note that the ...
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Bathroom Fan switch ground vs Neutral [migrated]
I'm sure this has come up before. I have been reading a lot about improper Neutrals or rather using ground as Neutral.
From what I can tell, the Neutral and Ground touch in the panel. I thought the ...
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Designing a simple UVLO in PSIM
I want to create a simple circuit in PSIM that does the same task as a UVLO (under voltage lockout) that only allows voltage to flow when the voltage is above a minimum level (e.g. 5V).
Since PSIM ...
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Find Vx in the given circuit [closed]
I used mesh analysis and got Vx equals 0 which I think is not possible . i2 = -2 , i1-i3 = Vx and 4-3i1+i3+2i2 = 0 are my findings
I have been struggling with this question for almost half an hour ...
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Finding equivalent resistance if each resistance is 100 ohms
The method to follow here is wye delta transformation, the resistors across red and purple nodes are in series so 2R and using delta to wye in green-pink-blue, and pink-black-blue
after that there are ...
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Implementation of Gain as a Resistance in an Integrator
I am trying to follow along with a thesis project block diagram but I am fundamentally confused as to how they have implemented the circuit.
The above circuit is a delta-sigma modulator but more ...
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Equivalent impedance of a circuit
I'm trying to figure out the equivalent impedance of the right side of this circuit (so the capacity, inductance and right resistance) :
I see this result in the solution of my exercice:
But I don't ...
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Why does an RLC filter circuit ring?
I have the circuit below.
I understand the concept of time constant in both inductors and capacitors.
The literatures says ringing because the signal resign in the pass band which have slope very ...
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Analysing the behaviour of inductor in the circuit
Suppose we have an L circuit with DC power supply of emf \$\mathscr{E}\$
simulate this circuit – Schematic created using CircuitLab
By KVL,
\$\mathscr{E}=L\frac{dI}{dt}\$.
This suggests that \$\...
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What is the best method for solving this circuit analysis problem in the S-domain?
I'm just curious what the best method for solving for voltage across the capacitor might be.
My initial idea was to use nodal analysis but I ran into a roadblock in that I am not entirely sure how the ...
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XL4016e1 maximum input current
I have an XL4016e1 dc-dc converter circuit,
the output of the circuit is 12V 6 A .
What should be the current value of the power supply to obtain this current?
thanks
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Thevenin Theorem Question
I am supposed to find the Thevenin equivalent of the above circuit. My method was to take the 33 ohm and 10 ohm resistors in series and turn that into a 43 ohm resistor. I then turned the 43 ohm ...
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ATmega32u2 example circuit sanity check
I'm working on a project and have decided to make it with the ATmega32u2. In the process I am trying to make an ATmega32u2 breakout board which only has the required components to run the device (...
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LTspice Monte Carlo Analysis Clarifications required
I am learning about LTspice MC analysis from this site. I understood almost all the things except the below one.
"Then make another spice directive to execute a Monte Carlo run as below
.step ...
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Simulation of current driving circuit not working
I am getting started on a variable current driving circuit design and just wanted to play around with some of the example circuits I'm reading about, but I never seem to get any meaningful current out ...
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Short circuit parallel to current source explanation
I was given this circuit in a circuit analysis course and found out using KCL/KVL that all the currents in blue are zero and Ix = -2A. I understand that the current source is connected with both ...
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Does Power Factor depend on circuit elements other than its own branch? [closed]
We know that Power factor = R/Z . . . . . This "R" and "Z" have to be the resistance and impedance of the elements in its own branch. But do the OTHER elements in the circuit ...
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Complex voltage and current
Someone can explain me the phenomena in rlc circuit. If we have an input voltage \$V_e = V_{max}\sin(wt)\$. Why the current resulting when it is written in books is not a complex number? And why the ...
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How do you calculate the total resistance in this circuit?
I stumbled across this circuit here and I don't really know how to approach calculate the resistance measured between A and B here:
I had a go at it but I assumed that I could "uncross" the ...
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How do I find the sign of V5A and V2VX in the mesh equations?
I do not understand how to know if V5A and V2VX is meant to be positive or negative in these equations. In the mesh 1, the current in going the opposite direction to the 5A current source and in ...
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Simple circuit analysis
I am trying to figure out what the output voltage (V1) of this circuit is. Is the photodiode in reverse bias in this case, which means the current is flowing in (opposite of what is shown here)? Is ...
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How to derive equation for current from parallel batteries given internal resistance and load?
I'm studying DC circuits in physics right now and have come across this frustratingly unclear part of the textbook.
Apparently, the current through a circuit given ideal emf, internal resistance, and ...
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How do I convert this spice code into a circuit of components?
I am looking for a piece of software which can take this spice code and convert it into a circuit of components.
The code is here:
...
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Resonance in AC circuits
Derive the frequency for resonance condition in the following circuit.
My perception is that I need to nullify the j part of equivalent impedence, is that correct?
Question:
My approach:
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Mesh or Nodal Analysis Problem
I was having an issue with the solution of this problem. I used mesh analysis with the equations, where \$i_{lamp}=i_l\$, \$i_{oven}=i_o\$, \$i_{heater}=i_h\$:
\$-120+120(i_l-i_o)=0 - (1)\$
\$-120+10(...
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How do I model the voltage of a capacitor being charged by a buffer?
I have a problem where I am trying to model the voltage across a capacitor in the following circuit:
We can see we have a reference voltage source of 1.25V driving a buffer. For T/2 the Capacitor is ...
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How do I solve for the total resistance of this circuit with two loops sharing a resistor? [closed]
The values are in ohms. The loop in question is as follows:
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I want to understand this circuit and these equations
I have a hard time understanding this circuit that I’ve been given because of the way it looks. I don’t know why, but electrical circuits seem very confusing to me even after reading the chapters to ...
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Getting V1, V2, V3 and the power delivered by the 2 voltage sources
Can you help me solve this one, I've been trying to solve it, however, I can't get it right. So far, I am stuck with this equation. Is this right? I am so confused to what I am going to do afterwards.
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Find expression for the current flowing through R2 at time t after S is closed
This question is from a coursework I had but is past its deadline, I really want to know the answer...
Refer to circuit diagram...
Essentially, I have to find an expression for the current flowing ...
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Diodes Problem - Forward or Reverse Bias
Hi, I am stuck on the solution to this problem. I understand that the second LED is in reverse bias due to its polarity, however, I do not understand how I can be sure LED1 is in forward bias. How can ...
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Thevenin Theorem Problem
I am struggling to find the thevenin equivalent voltage for the following circuit. I attempted using source transformation and mesh analysis by initially transforming the current sources into voltage ...
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What is the purpose of having a diode in a resistor divider supplying VGS of a MOSFET?
The purpose of the below circuit is to keep the output low during the ramping up period of V1.
simulate this circuit – Schematic created using CircuitLab
What is the purpose of Diode D1 and D2 ...
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Digimess dual linear PSU
Digimess (UK) seem to have gone to the wall, broken links on their website and phone line unobtainable. I wanted try and get the circuit diagram for my LM3002 Dual 30V 1A supply because the +ve side ...
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Linear circuit leads to quadratic equation
I would like to ask how to calculate the R1 and R2 in the following circuit.
I have equations
$$V_{out} = (I_1 + I_2) \times R2 + I_2 \times 10k\Omega$$
$$I_2 = \frac {2.5-V_{out}} {R_1}$$
which gives
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Resistance depending on voltage - the chicken and the egg?
If I understand correctly:
The resistance of some circuit components (like diodes) depends on the voltage across them.
When two components are connected in series: \$\frac{V1}{V2} = \frac{R1}{R2}\$
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How do I calculate current flow through a capacitor?
Currently I've only worked out on the time constant and Vo(t).
Time constant = RC = (4500 + 1500)×(10 μF) = 0.015 s = 15 ms
Vo(t) = 24×(1500/{4500+1500))
I used the voltage divider rule in this case, ...
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Construction of a Lagrangian function for a circuit
I was reading the paper "Introduction to quantum electromagnetic circuits", by U. Vool and M. Devoret and I am stuck in the construction of a Lagrangian function for the example LC circuit ...
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12V battery through a transistor then pump not working
I connected 12V to pump and to a transistor then connnected all of them to an Arduino:
It did not turn on.
I used this program:
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BJT amplifier design
I am trying to design a BJT amplifier with the given parameters and limitations. The circuit is shown below.
Parameters:
Vcc = 15 V
RL = 20 kΩ
beta = 180
Vbe(on)= 0.6 V
Cµ = Cπ = 0
Limitations are:
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Creating an iontophoretic circuitry design that is controlled by an Arduino Nano BLE Sense
I'm a beginner in analogue electronic design working on a project that involves interfacing a Arduino Nano BLE Sense microcontroller to a drug patch for iontophoretic transdermal drug delivery.
I can'...
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Why do we place a series resistor in the MISO signal of an SPI interface? What is the purpose of the and exact functionality of the series resistor?
I am working on a project in which I have to connect a 50R resistor in series in with the MISO signal line of a SPI interface.
My searches tell me it is used to match the impedance as well as ...
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Trying to perform transient frequency response with LTspice or Microcap, TL494 compensation
I have tried to do Bode plot of my uncompensated plant by myself in LTspice 17.1, but the result looks strange to me. This topic is a follow-on to this one.. I have no clue why it comes with 290 ...
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