Use this tag for circuits that only contain passive components, such as resistors, capacitors, and inductors. This includes RC, RL, LC, and RLC circuits.

learn more… | top users | synonyms (6)

-4
votes
0answers
61 views

working of the opamp Circuit [closed]

In the Following Circuit , how the opamp is working ? its not working as buffer. how the divider from 12 volts has stopped opamp from being a buffer ? thank you
5
votes
6answers
1k views

Measure temperature on a moving engine valve: transfer voltage and reading wireless?

I am an automotive engineer with very very little or almost zero electrical/electronics experience. I am working on logging real time temperature values on an engine exhaust valve and mounting a ...
4
votes
1answer
92 views

Alternatives to motorized variable capacitor?

I want to dynamically fine-tune the capacitor (about 100pF) of an RLC series resonant circuit, so as to keep it tuned despite variations of the coil's environment. Operating frequency is ...
1
vote
2answers
41 views

implementation different than simulation

I have to build the below series RLC circuit , and output its bode diagram using NI ELVIS Instrument Launcher. It is for a bandpass filter, so the output is taken across the resistor. Before ...
1
vote
2answers
32 views

Audio Mixer Passive Attenuator Circuit

I'm currently designing a digital audio mixer. One common thing found on audio mixers is a optional 20dB pad on the input. I've seen some attenuator circuits but all of them require you to know your ...
0
votes
1answer
40 views

parallel rlc voltage source

I am learning about circuits and I have some questions regarding circuit initial condition: - no initial energy stored before switch is closed - there is current at L1 at t = 0- I am wondering: ...
1
vote
2answers
25 views

Network Function of a Band-Pass Filter

So I've been trying to derive a the network function for a Band-Pass filter. I use voltage division to get a relation for the voltage output across the inductor. simulate this circuit – ...
0
votes
3answers
131 views

Operation of LC circuit in Frequency Modulation with simulation and linking it to the basic principle of frequency modulation [duplicate]

Can somebody help how message signal (words spoken near microphone) is modulated using LC circuit and how lc circuit oscillates at particular frequency by applying dc voltage. In the below circuit ...
1
vote
1answer
45 views

Multiple characteristic frequencies determined by one capacitor

I'm trying to figure out how to construct a filter with the following constraints. If it isn't possible, this would also be acceptable, albeit disappointing (and I would hope for some kind of proof). ...
0
votes
5answers
460 views

Resonance frequency of an RLC circuit

simulate this circuit – Schematic created using CircuitLab Is it safe to consider the resonance frequency of a second order RLC circuit to be alway equal to 1/sqrt(LC) or the transfer ...
8
votes
1answer
269 views

Does this oscillator have a name?

I found this oscillator schematic and I hope to find more information about it.
1
vote
2answers
77 views

What is the pole frequency of a three-phase LC filter?

Suppose I have this configuration: Assume L1=L2=L3 and C1=C2=C3. What is the pole frequency of this filter? Edit: As mcmiln says, this is not identical to the question here: Cut Off Frequency in ...
0
votes
2answers
81 views

RC circuit with two capacitors

Figure out the Vout wave form of the following circuit: ( assume the name of the 9u capacitor to be C2 and not C1) Is there any way to intuitively plot the waveform by understanding the behavior of ...
0
votes
2answers
57 views

How do you block a signal with a tank circuit?

I have a signal generator outputting 60 hz AC. I've connected the output to a capacitor (922uf) and inductor (0.0076H) which are in parallel with each other creating a tank circuit. These two values ...
0
votes
1answer
42 views

Impedance of a circuit that contains a 2 port network

simulate this circuit – Schematic created using CircuitLab So, firstly, find the y parameters of a network ( says the assignment). Which I did. Now for the impedance I get the a ...
0
votes
1answer
29 views

Noise figure of a passive network at a temperature different from room temperature

Given a passive network at room temperature, the noise figure is the ratio between the output noise power density pw and and the output noise power density due to the source pwS F = pw/pwS = ...
0
votes
1answer
45 views

How to find differential equation satisfied by \$u_{R_{equivalent}}\$, \$u_{L_{equivalent}}\$ or \$u_{C_{equivalent}}\$ in complicated RLC circuits?

When i'm given simple RLC circuits i know how to find the expression for each voltage, for example the expression of \$u_R\$ the voltage between the borns of the resistor \$R\$, or the expression of ...
0
votes
1answer
14 views

T-axis scale of a solved ODE

When I was calculating the following netwerk: Where given was: R=5,L=1,C=4,V_C(t)=10,I_T(0)=-2,V_in(t)=20. So the ODE that we get was: $$ \begin{cases} ...
0
votes
1answer
73 views

LC Tank Tuner for Super Regenerative Radio

There seems to be very little literature to explain the practical construction of a radio and how a super regenerative circuit actually act as a selector, amplifier, how a antenna is actually to be ...
0
votes
1answer
60 views

Understanding Resonant Frequency in a Series RLC Circuit

After spending a couple of hours on the internet searching for answers I'm hoping Stack Exchange can help me. Recently, using simulation software, I used an oscilloscope to calculate the resonant ...
0
votes
1answer
49 views

Non-resonant RLC band-pass filter

To create a band-pass filter using an RLC-circuit, i drew the following circuit (assuming R is given as 120): The corresponding transfer function is $$ H(\mathrm{j}\,\omega)=\frac{120\, C\, ...
0
votes
1answer
122 views

Measuring Q and Bandwidth of an RLC series circuit using Oscilloscope

I have a HNC Lab assignment coming up. As part of the prep for the lab work we have been given an RLC series circuit for which we had to calculate some values such as volt drop , Wn, Q and Bs, which ...
0
votes
1answer
74 views

Second-order Band-Pass Filter Gain Confusion

If I derive the equation for a bandpass filter (in this case, critically damped) from the RLC transfer function, I get a different result than I would get otherwise by combining the transfer functions ...
1
vote
1answer
58 views

What is the back voltage generated by this inductor in this practice problem?

The circuit is in a steady state, and the switch is lifted at t=0. In (a), i calculated the current i and the voltage v at the instantaneous moment that the switch is lifted. The current is 2A and ...
0
votes
2answers
69 views

time constant confusion of second order system

For first order systems, its easy to get the time constant by using thevenin concept. Suppose i have a second order system ,for example consider a two stage cascaded LOW PASS FILTER with identical ...
0
votes
1answer
89 views

In which of the LCR circuit the charge will decay faster?

Our instructor gave this problem. Cc << C. At time t = 0, the capacitor C has charge Q. In which circuit the charge Q will decay faster. Its answer is Charge Q decays faster in (A). ...
2
votes
3answers
347 views

What is the role of capacitor C3?

Here you can see the schematic of an LC oscillator. When I change the value of C3 it changes whether I have oscillations or not. For example if C3=10u there are not stable oscillations, and if ...
0
votes
1answer
61 views

In clamper circuit why RC>>T ? and why diode becomes reversed biased as capacitor becomes fully charged?

In clamper circuit why time constant is very very greater than time period of the signal i.e, RC>>T where R=resistance, c=capacitance, T=time period. why diode gets reversed biased as soon as the ...
2
votes
2answers
115 views

What does happen if the ratio of an ideal transformer is complex?

I have seen two solutions, both of then containing a paradox: Firstly, current and voltage ratio are inverse AND conjugate. In this first case, the two-port matrix is not symmetric (non-reciprocal). ...
1
vote
1answer
110 views

Loaded Q-factor of parallel RLC with series resistive load

So I have been studying resonant RLC-circuits, and have come to loaded Q-factors. At present I am trying to figure out the Q-factor of a circuit like this: simulate this circuit – ...
0
votes
1answer
47 views

LC Filter Attenuation

Hi I built a simple LC low pass filter and I supply it with a 1 volt peak to peak ac voltage at 200 Hz from a function generator. My cutoff is set at 700 Hz and I have selected my circuit components ...
0
votes
3answers
160 views

Getting resonant frequency in LC circuit with L as air core coil

im trying to find inductance of the air core coil,i read that in LC parallel circuit with known capacitor value we can find unknown inductance value by the formula so need to find 'f' resonant ...
1
vote
1answer
170 views

Filtering capacitors and inductors on power supply, how to choose and size?

I know this is fairly simple, and I get why these components are there. However, I do not fully understand why the certain values are picked and what the end filtering result is. Is the inductor in ...
2
votes
1answer
112 views

Power absorbed by a resistor in a crossed circuit

The given problem above is asking for the power absorbed by the resistor R given R = 1 Ohm. According to my professor, the two inductors do not cross so I redrew the circuit into the one shown in ...
0
votes
1answer
70 views

Why is the output of a series LC circuit sinusoidal?

How to analyze this circuit? Why is the voltage across the inductor(red plot) and capacitor(green plot) sinusoidal?
1
vote
1answer
65 views

Is the circuit a Parallel RLC if there is a voltage source in between capacitor and inductor?

simulate this circuit – Schematic created using CircuitLab As the schematic shows, there is a voltage source in between capacitor and inductor. Is it a valid Parallel RLC circuit. For ...
4
votes
2answers
682 views

LC Circuit problem!

Initially when the switch is closed ,at that instant the inductor is a short and capacitor is open ,so the diode cathode is floating ,so how does the diode conduct? Does the LC circuit resonate? ...
3
votes
2answers
146 views

What does a LC circuit in parallel to a speaker do?

I'm designing crossovers for my rear channels; a 2500 Hz 3rd order butterworth between an 8 ohm ribbon tweeter and two 4 ohm woofers in series (8 ohm load). While my original plan was to use two DPDT ...
-2
votes
1answer
167 views

Looking for Tables of Chebyshev I Lumped Filters, for Various Ripple values (in dB)

I have tables of Chebyshev I filter design only for 0.5dB ripple. I need the tables for other ripples. I can't find them on the internet. Could anyone point me to the right direction? Thanks in ...
5
votes
2answers
187 views

Why is this a 7th order circuit?

This is the circuit: I saw it in a book. It said that this is a 7th order circuit. From theory we know that the order of linear passive circuits is determined by the sum of capacitors and ...
0
votes
0answers
97 views

Guidance designing low-pass filter for audio circuit power supply

I'm developing a BeagleBone Black cape that has, among other things, and audio CODEC and 10 W amplifier. The “other things” include a connection to WS2812 LEDs, which generate a lot of PWM switching ...
0
votes
1answer
64 views

Calculating Transfer Function of passive circuit

I have the following passive circuit: I want to calculate it's transfer function \$V_{out}(s)/V_{in}(s)\$. My thoughts are: Part I: The voltage on the capacitor in the center (call it \$V_c(s)\$) ...
0
votes
3answers
102 views

Quasi-elliptical vs pseudo-elliptical filters vs Chebyshev Type 2 filters

Are quasi-elliptical or pseudo-elliptical and Chebyshev Type 2 filters the same filter response? Quasi-elliptical or pseudo-elliptical filters appear to be defined as "... filters with finite ...
1
vote
3answers
246 views

Passive filter design, transfer functions and loading

I have been playing around with some basic passive filters (first order), really just to try and get a better understanding of the equations and transfer functions. I was talking to someone about ...
0
votes
1answer
268 views

Passive audio phase shifter (180°) - can it be done? [closed]

I understand that most analog hardware phase shifting circuits seem to use OpAmps to get their job done. I am trying to build a tiny, non-powered in-line adapter for Mp3-players and such to quickly ...
1
vote
1answer
286 views

USB switching power supply filter

Good afternoon fellow students of life, I have a particular question that relates to the use of a Duracell USB switching power supply as the main supply for a high sensitivity sensor board. Most of ...
0
votes
1answer
125 views

Combined RLC circuit phasor diagram?

We have a circuit in the picture below. What will the phasor diagram look like in case: $$I_C<I_L$$ and $$I_C>>I_L$$ ?
0
votes
1answer
33 views

A LC parellel tank problem

Image a simple RLC circuit as below: The source Vs can supply an AC current 40A max., if L1 is absent, the current flows through C1 can achieve 40A. And with the adjustable inductor L1, I wonder if ...
-1
votes
1answer
80 views

What should be the source impedance and load impedance in LC filter design?

My aim is to generate analog signals with class-D amplifier. For that I am using the following configuration: Class-D-->Low-pass filter(LC)-->load(complex, real+imaginary) class-D amplifies my PWM ...
0
votes
2answers
69 views

Phasor diagrams for RLC series circuit?

So, here's the circuit: How can I make phasor diagrams for the circuit in case when $$I_C<I_L$$ and $$I_C>I_L$$ Edit: What made me confused is the current conditions, it's actually voltage ...