Questions tagged [analysis]
Questions attempting to analyze the mathematical properties of a formula, the inner workings of a protocol, or the design of a given circuit.
31 questions
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Why we use conjugate of current than the original phasor in the calculation of Complex Power i-e S=VI*
i have studied different books and sites for the above question but did not get the right concept that why the complex power encounter current conjugate not the original Phasor.if someone explain it ...
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2
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Thevenin equivalent resistance of circuit with diagonal resistors
I'm trying to find the Thevenin equivalent for part A of this circuit:
I begin by opening the circuit at the dotted line of part A. Then I try to find \$V_{oc}\$ across the two terminals that are ...
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1
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How do I find out which current/voltage to use for an unlabelled LED panel?
I have a 600mm x 600mm LED panel with 576pcs 3014-type SMD LEDs in some unknown configuration/topology (edge-lit, similar to this one here: http://i01.i.aliimg.com/wsphoto/v0/1990066259_5/Wholesale-...
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Alternative fix to: How can I calculate a Joule thief
This is based on the original question: How can I calculate a Joule thief.
Since the gain of common emitter voltage amplifier will depend widely on the
dynamic frequency of the LC unit, either way it'...
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3
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Z(in) for small signal analysis with BJT for unbypassed emitter and r0 in place
I have been studying the small signal analysis of BJT with re model with the emitter terminal not bypassed. I am able to derive those Zi, Zo,Av, Ai long as ro is assumed to be infinite. But I am ...
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Power amplifier input source current path
Can anyone draw (or write in text) the small-signal path from signal source XFG1 at input of Q1 base to amplifier load for positive and negative input signal swing?
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Puzzled by Nyquist frequency
Say I have a 1kHz sine, so no higher harmonics, then I need to sample it at least at 2kHz to be able to reconstruct it.
But if I sample at 2kHz, but all my samples are on the zero-crossing, then my ...
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Why does this circuit oscillate?
The circuit below is an oscillator. When I simulate it with ltspice, it does indeed generate a waveform (although it doesn't seem to be a very pure sine wave).
What I fail to understand is why it ...
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2
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How to analyze this diode circuit?
I am trying to analyze this simple diode circuit by hand, but I can't seem to get too far.
simulate this circuit – Schematic created using CircuitLab
Using circuit lab, it is evident that ...
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Predicting thermal equilibrium: what's wrong with my time constant?
I understand that this is arguably a peripheral electronics problem, but it seemed to fit here better than in physics.
I've been doing some power electronics design work with large IGBTs mounted on ...
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Reading a circuit
Disclaimer: I am a beginner.
I am reading a knol book on electronics, and I am faced with this schematics:
How do I read a circuit to understand what it does ? Do I have to imagine the electrons ...
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6
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Circuit analysis - software?
Surely there is some software that lets you draw a simple circuit diagram (DC voltage source and resistors) and then tell you the voltage, current, resistance, and power on R1, R2, R3, etc as well as ...
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1
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Type 2 compensation network
I'm working through the excellent text on SMPS design "Switching Power Supplies A to Z", by Sanjaya Maniktala. Right now I'm reading the section on the feedback loop and stabilization. As a first-...
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Proper assignations of current directions
What is the best way to know the proper direction of current? Lets say we have this circuit below:
The correct directions are given below:
What are your techniques to know which is the proper way? ...
- 2,523
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applying nodal inspection technique to supernodes with dependent sources
I was about to apply nodal analysis via inspection (to make it faster) to the above circuit, yet as we can see, it has a dependent source. So listing the equations for node(1 and 2) supernode a:
$$
...
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2
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Calculating an R-RC circuit
This is not homework. I have this circuit, and I want to calculate V2. I know it is equal to V1 at t=0, and equal to \$V1 \cdot \frac{R2}{R1+R2}\$ at t=\$\infty\$, but I don't know how to calculate ...
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How do I treat a PMOS compared to an NMOS in small-signal analysis?
What exhaustive list can I use to determine the differences between NMOS and PMOS devices when doing small-signal analysis?
Equivalently, what are the fundamental differences between NMOS and PMOS ...
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3
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4
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Equicalent circuit - RC // RC
I am doing a filter analysis of a simple network filter, requiring drawing some equivalent circuit to simplify the expression and analysis of the transfer function.
The issue I've got is regarding a ...
3
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1
answer
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How to calculate equivalent resistance?
This is not homework.
Imagine an infinite resistor grid which the picture shows a part of. The question is what's the resistance measured across any of the 1k\$\Omega\$ resistors. I don't want you ...
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Under what circumstances can impedances be simplified to simple resistances?
Consider the following circuit:
This is a simple first-order low-pass RC filter. The cutoff frequency is:
\$ f_c = \dfrac{1}{2 \pi (1k\Omega) (1\mu F)} \approx 159 Hz \$
The reactance of C1 at \$...
- 57.9k
2
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2
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Frequency dependent amplitude of a current source in an .AC analysis in LTspice
In my LTspice simulation I would like to integrate a current source in an .AC analysis which has an amplitude that varies over the simulated frequency spectrum, e.g. something like \$A(f) = {A_0 \cdot ...
2
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1
answer
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Derive transfer function from block diagram
I have this block diagram which I already reduced pretty much:
Now I want to derive the transfer function from phi_o1 to q. ...
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Nodal Analysis of an electrical circuit
I have several doubts about solving circuits.
Can any circuit be solved using Nodal Analysis?
If some circuit can be solved using Nodal Analysis, can it be
solved using Mesh Analysis too?
Why do we ...
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2
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Techniques for analyzing Comparator circuits?
I'm looking for some general guidelines/equations I can use to analyze circuits which use comparators. In particular, I'm interested in hysteresis.
For example, take the following open collector/...
- 17k
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1
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How to get started using ngspice?
I've recently finished some work with hspice, and now I don't have access to the server. I've installed ngspice on my Fedora 15 machine, but I'm unfamiliar with how it works. In hspice, I was able to ...
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1
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When to process beam forming algorithms?
I am building a system that uses beam forming to locate noises at different spots. All of the spots will be in front of the microphones (180 degree range of spots).
My first question is if the beam ...
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2
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What's passive about the passive sign convention?
I've heard and read about the passive sign convention, but don't really understand its meaning and importance in solving electric circuits. Is this because of conventional current which flows ...
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Find the DC component of a Full wave rectifier (DC Power supply)
I was asked:
Find the DC component of
---|Full Wave rect| -- Vr(t) ---|Filter| -- Vo(t)
$$ V_r(t), V_{dc} = ?$$
Where $$ V_r(t) = |V_m sin(\omega_o t)|$$
I know that the DC component of #$V_r(t)#...
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Analyzing effects of sixth order transfer function
This question is in relation to this question asked before (Settling time of sixth order denominator transfer function), but formulated in greater details.
So I have a transfer function which looks as ...
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2
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BJT with Zener diode
I got the picture from my prof's notes, and I don't quite understand why there can be two different currents at the given node. If there are only two currents shouldn't the currents' values be the ...
0
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1
answer
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AD620 - pot assembly alternative - filter
I have been posting questions regarding the AD620, reference voltge and output.
I followed all the instructions from Stack Exchange and voila! The circuit works like charm, thank you! It gives the ...
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