The analysis tag has no wiki summary.
13
votes
5answers
834 views
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 ...
9
votes
7answers
1k views
Differentiating between a square wave or sawtooth wave with a circuit…?
I want to build a simple sensor that takes a 100 kHz square or sawtooth wave with a known amplitude and outputs a high if it receives a square wave or a low for sawtooth.
I'm pretty sure this ...
7
votes
2answers
167 views
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 ...
7
votes
3answers
8k views
What's the difference between MOSFETs and BJTs (from a circuit analysis perspective)?
When analyzing circuits with transistors in them, when does it make a difference whether they are MOSFETs or BJTs?
6
votes
6answers
362 views
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 ...
6
votes
4answers
766 views
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 ...
5
votes
1answer
721 views
Circuit Analysis Shortcuts
I am slowly learning how to analyze circuits but I am wondering if my goals are unrealistic. My main reason is to help me repair circuits boards that I come across in my line of work. (I repair ...
4
votes
3answers
239 views
Time-series Statistical Analysis with FPGA
Suppose I have two time series, such as stock valuations or radioactive diagnosis, for which I need things such as covariances (QP -problem) among other things. Covariance calculations should be easy ...
4
votes
2answers
96 views
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 ...
4
votes
2answers
222 views
Frequency response - finding transfer function
I have a this circuit:
I am asked to find |H(\$\omega\$)| in its simplest form.
I approached the problem by first recognizing that the first op am was a standard inverter. With that I basically ...
4
votes
1answer
1k views
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 ...
4
votes
1answer
828 views
Questions about Thevenin's Theorem
I am reading up on Thevenin's Theorem and this has prompted a few questions that I hope somebody will be able to answer.
This is the tutorial I am reading.
The circuit below is then given as an ...
3
votes
2answers
97 views
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 ...
3
votes
2answers
278 views
Sniffing USB traffic at the hardware level
I've been looking to purchase a USB sniffer that will parse packets at the hardware level. I've used usbsnoopy and the like, but a filter driver solution is not my ...
3
votes
2answers
396 views
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 ...
3
votes
1answer
121 views
Identifying an irreducible circuit?
How would you go about identifying an irreducible circuit? By irreducible, I mean combining resistors whether in series or in parallel to reduce the circuit.
3
votes
2answers
155 views
3
votes
1answer
295 views
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 ...
3
votes
3answers
354 views
How to get fundamental frequency of a signal using autocorrelation?
I am trying to get the fundamental frequency of a signal that only has a single pitch. I coded out the autocorrelation function using FFT and already got the autocorrelation result. Unfortunately, I ...
3
votes
2answers
194 views
Nodal analysis for current controlled current source
Okay here I go. I just started learning nodal analysis technique but I feel its difficult in solving the circuits consisting of dependent current and voltage sources.
Im unable to solve this circuit. ...
3
votes
2answers
171 views
How to solve a transient circuit
Given this circuit considering that before the switch closes the network is in a steady state.
What steps should one follow to trace \$V_{L1}\$ before and after the closing of the circuit ?
As far ...
3
votes
1answer
119 views
equivalent load resistance
I have the following circuit
I am having some trouble determining the relationships between Iac, Io and Iacpk. I'm not quite seeing how the final equation for Iac was determined, specifically ...
3
votes
1answer
453 views
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 ...
3
votes
2answers
1k views
Supermesh Analysis of circuit of two loops
I have am having trouble moving forward with the following problem. The problem says that Find the value of Vs in the circuit below such that the power supplied by the current source is 0. The final ...
3
votes
2answers
258 views
Common gate amplifier with load connected to negative DC bias
What's the difference between the following two circuits? Note that the capacitors are DC blocking, and the FET is on.
I understand that usually, the load is connected to ground. But what would ...
2
votes
2answers
234 views
Simulation for a transmission loop using PowerWorld
I am now learning how to use PowerWorld Simulator. However, I faced some problems when I tried to enter the data given in the paper.
I want to simulate the following transmission loop:
First things ...
2
votes
2answers
99 views
Analysis linear ladder circuit
I'm trying to answer following question:
In the ladder circuit in figure 3, find the current, I, if \$V_s = 7V\$.
Use the fact that the circuit is linear. This can be done by assuming that ...
2
votes
6answers
204 views
Calculating Voltage
I am trying to calculate the voltage \$Vw\$ of the following circuit:
I have little experience with these kind of problems, so I tried to solve first a more simple circuit that did not include the ...
2
votes
1answer
96 views
How do I deal with square, cubic, etc. zeros and poles when manually drawing a Bode Plot?
I'm manually drawing a straight-line Bode magnitude plot. Say, I have the following transfer function in standard form for a Bode plot:
$$
T(j\omega) = \frac{1+j\omega/10}{(1+j\omega/50)^2}
$$
...
2
votes
2answers
175 views
Where can I find projects that are more tutorial than “copy-paste”? Some thing that talks about the math and analysis of it as well.
So, I'm taking 6.002x which is basic circuit analysis of resistor networks, MOSFETs, capacitors, inductors, diodes, gates, amplifiers, etc. and while I enjoy this I'm not learning anything about ...
2
votes
1answer
999 views
How do I decide which method to use in circuit analysis?
I'm an Electrical Engineering student, and circuit analysis can be really confusing to me. I sort of understand the concepts of solving circuits, but I don't really know when to use which method. Are ...
2
votes
1answer
155 views
nodal analysis, cant understand detail
this is a picture of the problem:
Can someone please explain to me, why is to \$V_1=V_2+10\angle{45°}\$
why not \$V_2=V_1+10\angle{45°}\$ or not \$V_1+V_1=10\angle{45°}\$
? ( it's circled in the ...
2
votes
1answer
288 views
How to conduct mesh analysis on a current source in series with a resistance?
How can I do a mesh analysis of the following kind of circuit? I'd normally put up Kirchoff's voltage laws for each of the two loops. If the current source wasn't in series with a resistance, I'd ...
2
votes
2answers
235 views
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 ...
2
votes
2answers
219 views
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 ...
2
votes
2answers
2k views
NPN Transistor Analysis: How is collector current determined?
I'm trying to understand NPN transistors by reading the chapter on them in Razavi's "Fundamentals of Microelectronics", and it says that collector current (Ic) is a function of the base-emitter ...
2
votes
1answer
1k views
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 ...
2
votes
1answer
662 views
Series to Parallel inductance conversion
Reviewing some material I thought I understood, but it turns out there's some subtlety I'm not getting. The usual formula for calculating the Q of a non-ideal inductor is \$\frac{Xs}{Rs}\$, where Xs ...
1
vote
3answers
147 views
Parallel resistor not affecting rest of the circuit
I have been asked the following question:
The resistance, r, is not known in fig(1a), why does its value not affect potential at b?
By Thévenin's theorem, any arbitrary voltage source can be ...
1
vote
2answers
185 views
What is failure analysis of PBCA?
I do not know whether this is the appropriate place to post this question but i guess its related to electronics. Basically i'm doing some research on what is the term for "PBCA" in failure analysis?
...
1
vote
1answer
234 views
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 ...
1
vote
2answers
193 views
Block Diagrams with offset in control theory
I have an equation in the form $$y = mx+b$$. In block diagram form, I could draw this with a proportional gain block and a summer. I was wondering if there are some clever tricks where I can make ...
1
vote
4answers
453 views
Circuit short circuit capacitor question confusion
I am really unsure about how to go about this question and which circuits to consider.
Here's the question:
Determine the value of the current labeled \$i\$ and the voltage labeled \$v\$ at ...
1
vote
1answer
151 views
What's passive about the passive sign convetion?
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 ...
1
vote
1answer
92 views
frequency modulation
I hope this is a pretty easy question for you guys.
I know for frequency modulation (FM) for fundamental frequency you have the expansion
$$output = J_0(\beta)V\cos(\omega t)\pm ...
1
vote
1answer
65 views
R-L Transients Storage Phase: “Inductors” Help?
The below expression is for finding the induced voltage across the coil (inductor) at a certain Time Interval. Furthermore, the additional expressions are to find the induced voltage at 1T and 5T. I ...
1
vote
1answer
179 views
alternative fix to: How can I calculate a Joule Thief
This is based on the original question: "How can I calculate a Joule Thief.
How Can I calculate a Joule Thief.
Since the gain of common emitter voltage amplifier and it will depend widely on the ...
1
vote
1answer
128 views
Negative voltage in Mesh Current Analysis
I am trying to learn about Mesh Current Analysis and have a question
I was reading this explanation on the subject from electronics-tutorials.ws:
...
1
vote
1answer
439 views
RC Circuit with Multiple Capacitors
I have been working on this problem and it is driving me absolutely crazy. The questions is asking for Vo for time greater than or equal to 0. I have successfully redrawn the circuit (shown below) to ...
1
vote
1answer
441 views
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 ...
