All Questions

Filter by
Sorted by
Tagged with
0
votes
0answers
61 views

Find the transfer function of an opamp circuit

I've the following circuit: simulate this circuit – Schematic created using CircuitLab I need to find the transfer function of this circuit. I did the following: $$V_+=\frac{R_1}{R_1+R_2}\...
2
votes
1answer
70 views

Transfer function of a summing integrator

I'm trying to derive the transfer function of a summing integrator for use in a feedback circuit. The single input and double input integrators are shown below. An integrator with one input is ...
1
vote
2answers
71 views

Is the following op-amp-circuit-in-the-Laplace-domain analysis correct?

I am relatively new to analyze circuits in the Laplace domain. So I decided to solve some problems as an exercise. Below presented a problem and my solution to it and I have two questions: ...
0
votes
1answer
70 views

Transfer Function of an Op-Amp Circuit

This circuit looks like an active high pass filter but without a second series resistor. What is it really? What is the transfer function Vo/Vi?
5
votes
3answers
152 views

Why the Wien Oscillator output is a sine?

I don't understand why the output signal of the Wien oscillator is a sinusoidal waveform. I can easily understand how a sine waveform can be generated by an oscillator which contains an LC circuit (...
0
votes
1answer
78 views

Recognised Op Amp Circuit?

I've had a bunch of op amp circuits do research and find the transfer function of, and this is the last one, does anyone recognise it? I've had a Sallen Key and an All Pass before, and wondering if ...
1
vote
4answers
159 views

Circuit inverts at high frequency and is unity at low frequency

Does anyone recognize this op amp setup? I've figured that at low frequencies C1 is as short circuit, putting the +ve and -ve inputs to \$V_{in}\$ and at high frequencies it will be as open circuit ...
0
votes
1answer
75 views

How to find the transfer function of this first order active filter?

Going through Design with Operational Amplifiers and Analog Integrated Cricuits, in Chapter 3, problem 3.4 I am asked: The circuit of Fig. P3.4 is a noninverting differentiator. (a) Derive ...
0
votes
1answer
81 views

Calculating the transfer function of this op-amp circuit

The first op-amp is a differential, second one is a follower and third one is a second order low pass filter. I've been struggling with the low pass and the final output of the circuit and I am not ...
0
votes
1answer
53 views

Low Entropy derivation of Transfer Functions with OP AMPS

I was recently low entropy equations of passive filters, and came across the Extra Element Theorem and all of its uses. I was wondering if the there is something similar for OP AMP circuits/ Active ...
0
votes
1answer
48 views

gain of inverting op amp with resistor on input

I´m trying to figure out the transfer function of the attached op amp circuit. I came to the conclusion that v_out = - v_in as as the two resistors in the upper path are equally sized, and the non ...
1
vote
2answers
84 views

Transfer function of Operational Amplifier

I am trying to solve the following operational amplifier circuit to get its transfer function. I have tried two different approaches, one is elementary approach by finding V- and V+ and equating ...
2
votes
2answers
3k views

Op-amps circuit with diodes

I am a beginner at electronics and I am trying to solve my first problems with diodes and opamps. I have to find and draw the output voltage uο related to the input voltage ui knowing that the voltage ...
1
vote
2answers
104 views

OP-Amp active filter analysis

Could you help me derive this transfer function for this OP-Amp circuit, I keep trying different methods and get no where close!
1
vote
3answers
2k views

Analysing a band pass sallen key filter

I'm trying to understand the transfer function of the band pass sallen key filter, which looks like: With the following circuit: How can I analyse it to get the transfer function? Thanks for any ...
0
votes
2answers
161 views

Transfer Curve of Amplifier

Can any one help me out to design a circuit with opAmp using this transfer curve? Here, OpAmps +V(sat) = 15v and -V(sat) = -15v
0
votes
1answer
95 views

Differential amplifier with two opamps

Recently, I was asked in a final exam how to do this. I tried to apply superposition but I think I am not understanding something in here. Does anyone know how to calculate the transfer function of ...
0
votes
2answers
107 views

Transfer function of an amplifier

Can someone please help me find the transfer function of this circuit. $$ \frac{V_0(s)}{V_i(s)}= \dots $$ simulate this circuit – Schematic created using CircuitLab This is what I have done ...
2
votes
2answers
161 views

Why isn't a 1 Farad capacitor equivalent to a wire in LTspice?

The following is a very basic driver circuit for one phase of a DC brushless motor. The input varies between -10V to 10V for a current between -2A to 2A. The amplifier is a power opamp from PowerAmp. ...
7
votes
2answers
167 views

Calculating the cut off frequency of a electronic filter

I've the following circuit: I know that the transfer function is given by: $$\mathscr{H}\left(\text{s}\right)=\frac{1}{1+sb_1+s^2b_2+s^3b_3}\tag1$$ Now, in this post they say that I can find the ...
0
votes
2answers
228 views

Transfer function audio pre-amp

On the picture above, you'll see a circuit. The exercise is to make a transfer function and draw a bode plot. I've tried to do that, but because there's no solution, I don't know if I'm right. ...
1
vote
1answer
149 views

Find transfer function and conditions to stability

I have this circuit in which I need to find the transfer funcion and the stability conditions. I first got confused because I only say the transfer function as Vo/Vi, not as Il/Vi as asked in the ...
0
votes
1answer
137 views

Simple current regulator transfer function

I did simple op amp MOSFET current source. It was not working correctly, it had oscillations as per picture, so RC circuit was was added and problem was resolved. What I am wondering is transfer ...
0
votes
2answers
715 views

Transfer Function for a Non-Inverting Op-Amp with Feedback

In the following problems, ideal op-amps are assumed. This op-amp circuit appears in Dorf's Modern Control Systems, 12th Edition (pg. 136): With \$v_{in}\$ on the left and \$v_{o}\$ on the right. ...
1
vote
2answers
2k views

Second order all-pass filter using a single op-amp

Is it possible to build an active second order all-pass filter using a single op-amp and no inductors? After Googling it I've found no less than three different circuit topologies, but when simulating ...
2
votes
1answer
282 views

How does a super diode work when the diode is directed towards the output of the op amp?

I saw this problem on a sample test and was stumped by the purpose of the diode. Since it's an ideal op amp, the 2 inputs (Vp, Vn) are the same. You know that Vp = 2Vi and so you also know that Vp = ...
3
votes
2answers
1k views

Designing a circuit from a transfer function

I have this transfer function of a bandpass filter with 2 poles and 2 zeros: $$ H(s)= 10^{-0.8} \frac{\left( \dfrac{s}{10} +1 \right) \left( \dfrac{s}{100.000} +1 \right)} {\left( \dfrac{s}{100} +1 \...
2
votes
5answers
489 views

Transfer Function of Inverting Ideal OP AMP with Parallel Combination T feedback network

I've been staring at this problem for two days now and can't get the correct transfer function. I've modeled it in Simulink (Matlab) and find the magnitude of the transfer function to be ~ $$H(s) = \...
1
vote
1answer
721 views

Frequency response of a non-ideal op-amp integrator (input bias current considered)

Consider the op-amp integrator circuit below. Calculating its frequency response the result is the following: $$ \underline{H}(j\omega)=\frac{\underline{V_a}(\omega)}{\underline{V_e}(\omega)}=\frac{-...
2
votes
2answers
758 views

Finding transfer function of a compensator circuit similar to a type 2 compensator topology

I know how to find transfer functions of op-amp circuits using equations derived from using Kirchhoff's current law (nodal analysis), and normally I don't have any problems solving them. However, I ...
1
vote
3answers
781 views

Opamp: determine the transfer function with negative RC feedback

I would like to find the transfer function of the above ideal opamp circuit. One of my approach was neglecting the effect of R2(assuming the voltages on the both side of R2 are the same) and applying ...
-1
votes
2answers
105 views

Transfer function for a OP-AMP [duplicate]

Can someone tell me if the transfer function for this circuit is: R2/[(w^2 * C^2 * R1) - jwC] thanks
0
votes
1answer
61 views

AC measurement in a circuit

I used the spice language to build an integrator op-amp, and one of the questions I had to address is to run an AC analysis on it. long story short- by looking at the transfer function of an ...
1
vote
3answers
1k views

Calculate transfer function of transconductance amplifier circuit

How can I model/calculate the behavior from Vin to Iout of the following circuit? (Credits of the picture go to Analog Devices): Essentially, I am interested in the large signal response, such as a ...
3
votes
1answer
459 views

Understanding in-loop compensation for capacitive-loaded OpAmp

I'm trying to understand the in-loop compensation for a simple amplifier loaded with a capacitive load, as seen in this article from Analog: http://www.analog.com/library/analogdialogue/archives/38-...
0
votes
1answer
528 views

What should be the polarities of the op amp input terminals such that the system is stable? [closed]

simulate this circuit – Schematic created using CircuitLab Ignore the - and + signs on the opamp (I couldn't erase it using the schematic), is it possible to determine the polarity of the op ...
0
votes
3answers
2k views

Calculation of transfer function in OP-AMP circuits

In a simple circuit like the following: simulate this circuit – Schematic created using CircuitLab I calculate the transfer function using I1 = I2: Vin = ...
0
votes
3answers
623 views

Find transfer function of Op Amp system

Trying to determine the transfer function for this Op Amp circuit using the rules that \$V-=V+\$ and that no current flows into the Op amp. I think that \$Vout=IR2\$ and determined the trasnfer ...
0
votes
3answers
717 views

DC gain of non-inverting integrator / Derivation of DC results from transfer function

(The pictured circuit contains a serious mistake, see my answer for more detail. I decided to leave the question in its original form for educational purposes, though.) Setting The (sub-)circuit in ...
4
votes
1answer
1k views

How do I realize a transfer function with multiple zeros?

I designed a compensation function for a control system in Matlab and now I'm trying to figure out how to build it using op-amps. I thought I might be able to use a couple of Sallen-Key amplifier ...
0
votes
1answer
82 views

transfer function of a complicated circuit

How to find the transfer function of this circuit? The addition of C_1 and another input function v_2 makes it more complicated Is it: \$Zout=\dfrac{R1}{1+R1C2s}\$ \$Z0 =\dfrac{1}{C0s}\$ \$Z1 =\dfrac{...
1
vote
1answer
265 views

Obtain transfer function of op amp circuit

I'm trying to find the transference function H(s) of the next op-amp circuit: I get the next following equations: When I put the equations together, this is an absurd. How do I solve this?
0
votes
1answer
855 views

Analog PID controller (transferfunction questions)

I have to build an analog PID controller (with op-amps), I've made a schematic: My questions: Can I build my PID controller this way? My PID tranferfunction (in the s-domain) looks like: $$\text{H}(...
0
votes
1answer
99 views

Given a transfer function i want an op amp represantation

I have a project for my university on the transfer function (where a,b,c are constants): $$G(s)=\frac{(s+a)}{(s^2+bs+c)}$$ and I'm asking how to represent this whole thing with an OPAmp circuit. (...
1
vote
3answers
272 views

Delay and Stablity in Negative Feedback Systems: Confusion-2

This question is in reference to my earlier question: Delay and Stablity in Negative Feedback Systems: Confusion In that question I wanted to ask why the second order system is always stable. But I ...
3
votes
2answers
418 views

Delay and Stablity in Negative Feedback Systems: Confusion

Below is a block diagram that shows an op-amp in negative feedback with feedback network made from resistive divider: The encircled block is Op-Amp with 1 and 2 as its inverting and non-inverting pin ...
3
votes
1answer
540 views

Sizing capacitor across op amp inputs

I'm studying the constant current portion of the schematic for the Agilent E3610A DC Lab Power Supply, redrawn below for reference. The current reference supply develops a negative voltage \$V_{CREF}\...
0
votes
3answers
85 views

Simulating a tranfer function with opamps

I am asked to simulate the following transfer function using operational amplifiers: Obviously what it evokes is a second order filter, my question is what kind of filter should I use (Butterworth, ...
0
votes
1answer
706 views

How to derive the transfer function of the Inverting Summing Amplifier?

I know that the transfer function of an inverting summing amplifier gives this, by using the Superposition principle: (for example with 2 input voltages) \$U_{ out }=-(\frac { R_{ 1 } }{ R_{ f } } U_{...
0
votes
1answer
281 views

Unipolar op amps

Ex : My question is since it's a single supply op amp, does this mean that we can't generate negative voltage so the transfer function would bottom at 0?