# Questions tagged [circuit-analysis]

Circuit (Network) analysis is the process of finding the voltages across, and the currents through, every component in the network.

3,258 questions
Filter by
Sorted by
Tagged with
85 views

### Why the DC voltmeter does not read zero when it measures an AC signal?(Chua's circuit)

I have made a Chua's circuit that is nearly the same as the one in Kennedy 92(pdf). I don't have an oscilloscope yet, so I connect a DC voltmeter at the place where probes of oscilloscopes should be ...
32 views

### Is the value of the inductor important in chua's circuit?

In Kennedy 92, the author gives a worked example of Chua's circuit experiment. The circuit diagram is given below: The author (in section 7.1) discuss how the value of each component might be chosen, ...
1k views

### How to calculate the Impedance of a circuit

I am having a problem regarding calculating the impedance of the two circuits below: simulate this circuit – Schematic created using CircuitLab Everywhere I search I always get a description ...
33 views

### RC Circuit Analysis - Finding Capacitance

I'm lost on how to approach the following problem (apologies as I'm not an EE). In the following circuit, I'm trying to find the capacitance that will limit the node voltage (where the voltmeter is ...
54 views

### Power Supply of a VCR [on hold]

My VCR was not working, I wanted to restore it. I don't have enough knowledge about circuit components. Can you tell what it that white round colour thing in the picture?
36 views

### Calculating currents and powers on three phase 4 wires system

What do I use for phi in power equations?
2k views

### Crowbar circuit causes unexpected behavior for op amp circuit

I am using an op amp to amplify an input signal from a microcontroller, which in general is working fine. For over voltage protection, I added the crowbar circuit taken directly from figure 32, page ...
35 views

### Parasitic insensitive switched capacitor circuit

I'm trying to simulate the parasitic insensitive switched capacitor circuit shown here: I am using cadence virtuoso. My input is a sine wave of 1 V amplitude, 0 DC and 1 kHz frequency. I am using ...
38 views

### Three phase systems - when is potential of a star node equal to zero?

I had to find total impedance of the following three phase circuit with symmetric line voltages: I've been told that nodes 1 and 2 can be connected because their potentials are equal (zero).After ...
154 views

### Calculate the capacitor voltage for t < 0 and t > 0 for the circuit below

Please help me calculate this. I tried using the thevenin equivalence method however I'm not familiar with two independent sources in a circuit. When I was simplifying using thevenin method the ...
53 views

### Proof of the superposition theorem in linear circuit analysis

I couldn't find a proof of the superposition theorem from circuit analysis anywhere online. I thought it might be helpful to ask and provide my proposed proof as an answer to gather feedback and ...
123 views

### Why does there flows no current through the common part of the circuit?

I saw there was a post asking the same question here but I still don't understand it. I am reading the book Code: The hidden language of computer hardware and software and the book shows the ...
83 views

### please explain this fourier equaton

reference from here why are there 2 exponential terms on right side of equation in red box ? i know euler identity but why does ,the left side is trigonometry form when n=1 equal to exponential ...
106 views

### Basic circuit analysis?Which are parallel?

I think there are 6 nodes(as I've labelled in the picture),8 branches and 6 loops in the circuit.But which resistors are parallel to each other?R7||R4,R2||R5||R3 + R6 ?I'm really not sure.Can someone ...
41 views

### Can I represent this circuit like this

I want to do even-odd mode analysis, is representation of the circuit as shown below correct? Are these two circuits equivalent. Z is the characteristic impedances and theta are the electrical length ...
39 views

### Designing a rechargeable circuit for phone

I'm currently working on a project where I'm looking to design a circuit that will charge my phone by utilising a slim lithium battery that is rechargeable. I've achieved the rechargeable aspect by ...
97 views

### CMOS Inverter Circuit Analysis

So I have a circuit shown below, that looks to me likes it's a CMOS inverter circuit. In this question, we're asked to find the current and voltage across drain-source voltage of the NMOS component. ...
147 views

### Power Line Communication

I am using an emitter and a receiver circuit in order to communicate through the power line. The receiver circuit I am using is shown at the figure below and it uses the LM567 tone decoder to decode ...
187 views

### How to find new ABCD parameters when reversing 2-port network

I have an ABCD matrix represenataion which is defined as: For such a problem, what approach should I follow in order to organize the new ( reversed) network ports voltages and currents properly. I ...
72 views

### Is there a way to save my electronic microscope which received 9V instead of 5V [closed]

I plugged in by mistake a 9V charger into my expensive :( 5V electronic microscope. (no warranty) The screen turned 100% white. But now with the correct cable 5V 1A, the screen stays black. (But the ...
158 views

### Calculating gain of ICF amplifier

I'm designing a circuit with an ICF (indirect current feedback) amplifier, and am trying to calculate the gain of the resultant circuit. Using the AD8237 I followed the example here when designing ...
29 views

### What is the working and reactive power in this circuit

i need help with solving this task (it's on croatian but i will translate): https://ibb.co/sb0cnsx ,it says what is the the working and reactive power for the given cirucit (Xl = 3 ohm ,Xc = 2ohm R = ...
28 views

### Which of these two are correct? Even-odd mode analysis of Power Divider

That rectangles represent transmission lines and Z is the characteristic impedance. In even-mode the plane of symmetry becomes open circuit. Could you please tell which one is correct of this two ...
337 views

### Q: How to remove DC offset

simulate this circuit – Schematic created using CircuitLab Essentially my goal is to measure Node A and feed Node C into the arduino for further measuring. What I attempted was use a buffer ...
105 views

### Network analysis… Nodal analysis

Is nodal analysis should be applied only when circuit containing current sources..? Or otherwise we have to use source transformation.. When any voltage source is present in the circuit..?
45 views

### 5V vs. 3V diode protection circuit

I'm using USB cables in an very unconventional way (don't ask, we had a barrel full of USB cables left over from something else) to connect between boards with 3v battery power and also not following ...
50 views

### Ćuk Converter circuit analysis

I am confused by the current path of the Ćuk converter when it is at position one where the mosfet is conducting The circuit analysis results in the two circuits below. What is the current path? Why ...
1k views

### LT-Spice RL circuit simulation ill behaved current

I am trying to simulate a RL circuit in DC with LT-spice as follows: NOTE that the inductance is 0.0229 H although in the picture you see 229 Now, according to my calculation, what I would expect is ...
16 views

### Transient time in buck converter

To my understanding the reactive components in a converter should not store energy over a switching period, otherwise they will blow up. An in inductor for example abides by volt-second balance, which ...
54 views

### How does an 8Vac Power supply charge a 3.6Vdc battery pack? [closed]

The charging circuit consists of the 8Vac power supply, the battery pack with 3 Ni Cd batteries, and a 4-inch-long component. One lead from the power supply is connected to the positive terminal of ...
47 views

### Please explain these RLC transient equations

simulate this circuit – Schematic created using CircuitLab From my book Assume the capacitor is charged to a voltage V0, and then at t = 0, the switch is closed. \begin{gather*} \frac{1}{C}\...
52 views

### Difficulty in understanding the paragraph concerning h- parameters

This is a paragraph from "Engineering circuit analysis" by W H Hayt. I really don't understand the statement "it is difficult to open circuit the open terminals...." What does he mean in the paragraph?...
68 views

### How to work out this implementation of chua's diode?

The author of a book claims that this is the implementation of Chua's diode by [Kennedy, 1992], although I cannot find this article. My question here is, how does this circuit work? For me, the ...
93 views

### 220v to 9 v transformerless power supply [closed]

I wanted to turn 220 volts to 9 volts in order to turn on a touch switch , so i used the circuit below but there was a warning in the description which mentioned not to touch the circuit at all , is ...
97 views

### Why can RLC resonance be dangerous for electronics

There is a lot of information about RLC circuits and resonance, and many times it is mentioned that when a series (parallel) circuit resonates, a really high voltage (current) can be found across the ...
141 views

### Finding the primary VA when winding your own power transformer?

I have been researching how to build power transformers but I am stuck on finding the proper wire gauge for winding the primary. In order to find the correct wire size I have to know the current in ...
45 views

### Microphone input buffer circuit not behaving as in simulation

I have designed a circuit to interface the SPW2430HR5H-B microphone into a dsPIC33 ADC pin. The circuit has an active LPF and uses the AC coupling capacitor as a HPF to get an output on the frequency ...
54 views

### How to emulate the signals of my joystick? [closed]

This is the circuit diagram of my joystick: Once these signals are transmitted and arrived at the radio receiver, the signals can be read in the CAN bus. One can easily modify the message on the CAN ...
211 views

### 555 timer not switching at threshold voltage

This is a 555 timer circuit which is supposed to generate two short pulses, back to back, at a regular frequency. The top 555 is configured as astable to control the frequency. It feeds the first 555 ...
59 views

### How to solve this transient circuit?

Could anyone explain why in this example $I_t = (\frac{12}{5} - \frac{24}{2})$? It is my understanding that it should be $\frac{12}{5}$ because of the initial condition of natural response.
123 views

### Add tilt switch to this photodiode circuit

I'd like to take this phototransistor switch circuit: And add a tilt-ball or similar switch in series. That switch needs to be heavily debounced, so that it stays "switched" more or less for several ...
11k views

### 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 ...
85 views

### How many NPN common emitter transistor circuits are there? [closed]

I'm studying for an important exam, solved a lot of common emitter circuits with different unknowns. Most of them them look similar. Can someone give me some examples or exercises of circuits of NPN ...
136 views

### Have i understood voltage correctly?

I am not from an engineering background, so this may be very simple and stupid but: Voltage is the difference in electric potential between 2 points Voltage drop describes the reduction in energy of ...
44 views

### MOSFET Capacitance clarification

2 part question here. Are there ways to directly test the input and output capacitance of a MOSFET, Ciss and Coss? On that note, due to internal inductance and capacitance, is it possible for a ...
57 views

### Simple RC Circuit question: how does a precharged capacitor interact with a lower voltage source?

So, I have this simple question to solve, but I am uncertain about some details. The circuit I have to solve is the one on the image below: I have a circuit with one capacitor(C = 1/4 Farad), two ...
18 views

### Complex vectors E and H

I have a doubt about the physical meaning of the complex representation of electric and magnetic fields. Let's consider an electromagnetic wave, in which both electric and magnetic fields propagate ...
151 views

### Voltage across an resistor

In the figure shown, Vi is a 100 hz triangular wave having a peak to peak amplitude of 2 volts and an average value of 0 volts. Given that the diode is ideal, the average value of the output voltage ...