Questions attempting to analyze the mathematical properties of a formula, the inner workings of a protocol, or the design of a given circuit.

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1
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3answers
72 views

How can the FFT analyze a wave in which the components are changing?

Based on what I've read about Fourier Transforms, it seems that they are designed to work on waves whose components are constant. For example, a simple square wave is \$\sin(\theta) + ...
1
vote
0answers
60 views

How to analyse periodic data obtained from a vibration experiment? [migrated]

I have data from a vibration experiment on a structure. This data was obtained by attaching an accelerometer to a FFT analyser, which records the data at a high sampling rate (typically in kHz range) ...
7
votes
8answers
1k views

Engineering Electronics: which approximation is usually good enough?

I have a strong computational background, so approximations with floating point precision depend on the type of computation. One thing is to know how to make an approximation and another one is when ...
3
votes
1answer
118 views

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: ...
0
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0answers
21 views

Time independent sampled data systems

The following discussion I'm assuming that the plant has no dynamic component and is just a constant gain, with perhaps a one or two sample delay. The closed loop system can therefore be completely ...
0
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0answers
28 views

Deriving current gain and voltage gain for common base BJT

For a common base configuration BJT such as the one shown here: http://i.imgur.com/M9LtHoW.png How can I derive the voltage gain and current gain? I found the answer on Wikipedia but all my attempts ...
0
votes
1answer
66 views

Question on DC analysis of BJT - Common Base

I'm trying to solve a question from my book. The answer for the question is given but I keep getting a different answer. I don't know if I'm doing it the wrong way or the book is wrong. This is the ...
0
votes
2answers
123 views

Circuit analysis and general study tips [closed]

The more work I do in the field of EE, the more I realizing that my general circuit analysis skills are usually the root of my confusion and could use improvement. Even after putting on my ...
1
vote
2answers
87 views

Is there a way to solve this circuit using Nodal Analysis?

Please, take a loot at this circuit: Obviously, this is a circuit that is very easy to solve using lots of different methods. However, I'm trying to solve it using Nodal Analysis (I'm not sure if ...
1
vote
2answers
131 views

Help with DC circuit theory problem

I need help with this DC circuit problem: When the switch is open, voltage between points A and B is 2V. When the switch is closed, through variable resistor \$R_{p}\$ flows maximum current, and ...
0
votes
0answers
33 views

Does the choice of ground/reference node influence the results found with nodal analysis?

I'm currently taking my EE introductory course about circuit analysis and I'm having some issue. I felt like I had finally understood how to (somewhat) properly perform Nodal Analysis. I attempted to ...
1
vote
2answers
113 views

Nodal analysis - what to do when a supernode spans entire circuit

I'm back again with a nodal analysis question. I'm getting better, but I've come to a problem again. Consider the following circuit with the bottom node as ground: I specifically don't know how to ...
2
votes
1answer
124 views

Nodal analysis - how to handle two adjacent supernodes

I'm a first year engineering student who has a problem with harder nodal analysis problems. Consider the circuit in the attached image. The usual way to deal with the voltage sources in the upper ...
2
votes
3answers
400 views

Thought Process on Designing Circuits

I'm currently in my second year of computer engineering. I've taken circuit analysis courses and have a good general understanding of components, and a little bit of digital design, however, I'm very ...
1
vote
0answers
81 views

I'm trying to determine the Thevenin voltage of a circuit using the node voltage method

I'm trying to determine the Thevenin voltage between the terminals a and b on this circuit: Notice that I've named the three essential nodes \$v_1\$, \$v_2\$ and \$v_3\$. I've highlighted the ...
2
votes
2answers
123 views

DC analysis of common source MOSFET circuits to find gate voltage using different power supplies

simulate this circuit – Schematic created using CircuitLab strong text I am solving problems on DC analysis of MOSFET circuits. We are supposed to find various parameters like Id(Drain ...
1
vote
1answer
240 views

Since the z-transform of the zero order hold is 1, why bother including it in analysis or simulation?

The \$z\$-transform of the zero order hold is 1. So why should it even be considered in the discrete time analysis or simulation of discrete time control systems? ...
0
votes
0answers
24 views

Application of SIMPLIS POP analysis to converters with AC input

Is there any restrictions on switching frequency of the converter? SIMPLIS help says: Converters with AC inputs will only POP under very specific circumstances. These requirements are: ...
2
votes
4answers
3k views

How to change the frequency of AC supply?

Im using an inverter to convert Dc into Ac from battery. I want to control the frequency of the alternating current ie., increase and decrease gradually (eg: 1Hz 2Hz 3Hz... 60 Hz). Is it possible to ...
-1
votes
1answer
62 views

AC Analysis Mindset [closed]

I'm just trying to solidify my foundational knowledge of ac analysis. So when approached with a basic circuit, lets say a RLC circuit, should my first instinct be to convert each group of components ...
0
votes
3answers
143 views

Different time constants for charging and discharging of modified RC circuit

I recently performed a test in an electrical measurements lab which left me confused. I measured the response of the following circuit: And obtained the following output: According to my ...
3
votes
2answers
266 views

Av for small signal analysis with BJT for unbypassed emitter and ro in place

My question is about another question on this site. On that question Z(in) for small signal analysis with BJT for unbypassed emitter and r0 in place Zin is asked for a common emitter configuration ...
0
votes
0answers
61 views

transient analysis in aim spice

How do I carry out the transient analysis of series RLC circuit using AIM Spice? I can't figure out what values should be given for step size and final time. Also, I was seeing some tutorials and ...
-1
votes
1answer
58 views

analysis square waves oscillator: how do I calculate the values?

Which are the Vc (V+) and V-, I's and Vout values in these circuits? The node i's and the Vc and Ic?
1
vote
2answers
91 views

What is the sign convention for generated power?

Generally speaking, generated power is denoted as negative, correct? If I understand correctly, this is just the convention. Conceptually, I think of it kind of like a force, it has a magnitude and ...
3
votes
2answers
841 views

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 ...
0
votes
1answer
60 views

Should I assign currents to voltage sources in my circuit analysis

Mortals! I apologize if my question may seem, foolish, but I have a need of understanding a process in analyzing circuits. You see, when we are looking at resistors (non-sense, my lightning never ...
1
vote
1answer
50 views

PMDC Motor transfer function

I'm doing an analysis of a PMDC motor and I don't understand something about the transfer function. I have the following equation: \$(K_t\frac{1}{((s* L_A) + R_A)})(V_I(s)-k_b\omega(s))= ...
2
votes
2answers
252 views

Poles in electrical engineering

I'm currently an undergraduate electrical engineering student who recently took an elective mathematical course on complex analysis, where we learned about all kinds of singularities for complex ...
1
vote
1answer
647 views

Superposition Theorem/Nodal Analysis

I'm having a little trouble understanding this worked solution. My understanding of superposition is that we "turn off" every independent power source except the one we plan on analysing, then we ...
0
votes
1answer
39 views

Finding the Current I1 using Polar Notation

For the circuit in Figure Q3. Convert all voltages and currents to the form X sin(t + φ ). You need only find the stead-state solutions. Solution My Steps ... It seems that I am going along ...
1
vote
1answer
256 views

Using Pspice to analyze BJT transistor

As always I have a rookie question. In a project, I need to analyze the circuit below in a way that the transistor would be in forward active mode. I need to calculate resistors and voltage sources, ...
5
votes
1answer
133 views

What's wrong with my boost converter math?

I'm working some equations for a boost converter, and running into a contradiction I don't understand. Assume a steady state, perfect efficiency, and continuous conduction. Total instantaneous ...
1
vote
2answers
130 views

Link between zero state response and the particular solution for an everlasting exponential input

In an LTI system, when the input is the characteristic function (i.e. an everlasting exponential function say \$e^{st}\$ ), the ZSR which is obtained by the convolution integral with \$h(t)\$ is ...
3
votes
2answers
7k views

Diode circuit analysis using ideal diodes exam problem

I've been reviewing some past exam and stumbled across this question So I need to find the current I through the middle diode and the voltage across the bottom left 10KΩ resistor. To try solve this ...
0
votes
1answer
164 views

How to do derating analysis

I need help in learning derating analysis for a vienna rectifier circuit (may be anything). Do you guys suggest any material to do the derating analysis by hand for each component understanding the ...
0
votes
1answer
2k views

Using an LM331 as a frequency to voltage converter, how to set frequency FSR?

I'm trying to use an LM331 in a frequency to voltage converter configuration. LM331 block diagram: I'm trying to implement this circuit from the datasheet for a supply voltage of 5V and an input ...
-1
votes
1answer
97 views

Identifying this “Transistor”, in this particular circuit [closed]

I'm in FIRST robotics, and I've been helping with our robot over the past few weeks. Every robot (in FIRST) is required to have a status light, which is fancy-ily connected to some other gear. ...
2
votes
1answer
110 views

How to interpret this bode diagram

I have this bode diagram. I am wondering how to interpret this. We start off with 90 degree phase lag e.g. a integrator. Then at approx 12 Hz we drop another 180 degrees indicating two integrators. ...
2
votes
1answer
196 views

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. ...
1
vote
1answer
256 views

Can't figure out voltage-controlled current sources

I'm trying to teach myself how to wire circuits, but I don't know if I got the correct answer for this? Where is a good place for me to learn the order of operations for solving circuits? Thanks.
3
votes
2answers
144 views

Thevenin analysis

I have a hard time understanding why Thevenin analysis works. I can see the math, and I can find the equivalent resistor, but I am not sure why it is a valid analysis from a practical point of view. ...
0
votes
1answer
53 views

Pulse-excited integrator reaching infinite potential?

I was given the following Op-Amp circuit to analyse and to find the potential V_out as a function of time, with V_in defined as the Heaviside step function: $$V_{\text{in}}=\begin{cases}0\mathrm{V} ...
1
vote
1answer
192 views

Diode small signal model and exponential model comparison

I'm working my way through the chapter on diodes in Sedra and Smith Fifth Edition Exercise 3.15 asks: Consider a diode with \$n=2\$ biased at \$1ma\$. Find the change in current as a result of ...
1
vote
0answers
81 views

Not seeing set_address packet using USBTrace

I'm currently exploring the wonderous world of the USB Stack. I'm using a PIC18F2550 and the USB IO example available at www.moty22.co.uk. The code works as expected, but when using USBTrace (or any ...
2
votes
1answer
639 views

Theoretical break frequency and bandwidth of notch filter

I'm trying to learn how to calculate the bandwidth and break frequency for the notch filter shown below. I was told that wye-delta and delta-wye transformation would be needed, but don't fully ...
8
votes
1answer
397 views

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 ...
1
vote
1answer
141 views

Complexity comparison of an adder and a multiplier

I have two algorithms with different requirements of addition and multiplication operations as follows: Algorithm 1: 100 additions 200 multiplications, total = 300 operations. Algorithm 2: 300 ...
0
votes
1answer
293 views

Sequential Circuit Diagram: D Flip-Flop

Sequential Circuit Diagram: D Flip-Flop Answer Key ...
1
vote
1answer
165 views

Can I use a Bus Pirate to drive this VFD?

So a few months ago I asked the question on how to analyze a display. Since then I have found out much information about this board. From some trace following it seems that Brown - DATA Red ...