Questions tagged [transfer-function]
Anything related to transfer functions, i.e. those complex-valued functions of a complex variable used to model mathematically the I/O relationship of linear time-invariant initially-at-rest system using Laplace transform.
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RC Filter Analysis
Let the following circuit:
I was looking at some old youtube videos, explaining how obscure this simple looking circuit, here is my question, suppose that the AC voltage source \$ v_i(t) = A \sin(\...
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The bode plot of proteus simulation and matlab transfer function is not same
I am trying to calculate bode plot of a circuit.
For proteus my frequency at -63dB is 18 kHz as sample the circuit connection and its bode plot is provided.
Using analytical approach I calculate the ...
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How to find the transfer function of current H(w) = I_out(w)/I_in(w)?
How do you find the transfer function $$H(\omega)=\frac {I_\text{out}(\omega)}{I_\text{in}(\omega)}$$ of a circuit like the below?
simulate this circuit – Schematic created using CircuitLab
I ...
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If I have an operational amplifier with a finite open loop gain, can I calculate the transfer function neglecting the open loop gain? [duplicate]
I'm talking about this op-amp. In the solution it finds an expression for the transfer function using a virtual short circuit without considering the open loop gain \$ A_{vol} \$ at all. I wanted to ...
user386995
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Realize transfer function with Op-Amps
I have this transfer function:
$$
H(s) = 15 \cdot \frac{(1k)^2}{s^2+500 s+(1k)^2} \cdot \frac{s+40}{s+300}
$$
I separated it into two stages, diving the \$k=15\$ so that both transfer functions have ...
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Derive S-Parameter Matrices for Interconnected Multi-Port Networks of Arbitrary Size
Question(s)
Is the math below correct?
If not, then what should be changed?
If you know of an authoritative reference for this derivation, then please post it in an answer, or in the comments.
...
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How should I apply FACT technique on this circuit?
I am learning the fast analytical circuit technique. How could I calculate the pole in the circuit below? I also calculated in the "traditional" way.
I was able to determine the zero and ...
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Determining the zeros and poles of a common emitter amplifier
I want to determine the transfer function of the base common emitter amplifier. I don't want to neglect the impedances of the capacitors in the calculations because I want to determine the zeros and ...
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Disturbance error transfer function
I was trying to solve some examples from the book Feedback Control of Dynamic Systems by Franklin, Powell & Emami-Naemi. (Seventh Edition, Pages 195 & 204) about PID controllers. The problem ...
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Derivation of the AC small-signal circuit and the canonical form of a DC-DC buck converter
I'm new to this forum and hope you can help me. I am in the process of designing an input filter for a DC-DC step-down converter 12V-5V/1A (Pic.1).
I am trying to determine the transfer function and ...
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Calculating the poles of a Circuit
I have been reading Behzad Rahzavi's Analog Design book to prepare for interviews and have come across a discussion on calculating poles that confuses me.
In the following example 6.15 the book ...
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Solving complex opamp circuits
I'm having some troubles understanding how to solve complex circuits with opamps like the following:
During my lab course (I'm a physics major) the professor showed us the solution of very simple ...
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How can these passive RLC circuits change a sinusoid's frequency?
Given a sinusoid input of frequency f, an RLC network, no matter how complex, should produce a sinusoidal output of frequency f, with possible attenuation and phase shift. At least that's my ...
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What signal to use for identifying control-to-output TF of resonant converter? Is it required to have a transfer function when PI tuner is present?
I have a resonant converter (DC-AC) built on Simulink and I want to find out its control to output (current) transfer function using the system Identification toolbox in MATLAB/Simulink. I have three ...
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Transfer function for optocoupler
I read application report from Texas Instruments:
Practical Feedback Loop Design Considerations for Flyback Converter Using UCC28740 (SLUAA66)
There is a schematic (Figure 4. Optocoupler Frequency ...
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Maximum Power Transfer Theorem Question
I'm missing something here. The maximum power transfer theorem states that max power transfer from source to load happens when source impedance matches load impedance.
In the case of a 10V source ...
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Finding Deboo's integrator time constant and transfer function
I tried to determine the transfer function and time constant of Deboo's non-inverting integrator. If I calculate with an ideal op-amp, then my calculation fails if the ratio of R2/R1 and R4/R3 is the ...
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In this transfer function equation, is "20" inside the log() the value that was factored out?
In the given problem, we're supposed to find the gain of the transfer function. The solution provides an equation to the problem. The question I have is, for that particular equation, is the value ...
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Is it possible to simulate reflections by designing an RLC transfer function?
Assume that you're knowing the PCB stack and the geometry of the conductor.
You're computing the capacitance per mm and inductance per mm and also the total resistance of the conductor.
That means you ...
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Why is inverse of a transfer function not really a correct way to think while doing circuit analysis?
When we try to predict the circuit behaviour using transfer function, everything works fine in forward direction (Vin to Vout).
But if we try to predict the circuit behaviour in reverse direction (...
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Oscillation criterium of UcD (Universal Class D) amplifier
This Paper written by Bruno Putzeys describes the operation of an Ncore/UcD amplifier.
On page 2 the author presents the following formula, which he previously used to determine the approximate ...
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Plotting the bode plot of a high pass filter using matlab
I am trying to theoretically find the frequency response of the circuit given below:
Firstly i found the impedance value of the RC Ladder by applying the equation below, then i defined this as "...
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Setting 'H' in the Chebyshev approximation
For the Chebyshev approximation, \$ \frac{V_0}{V_{in}} = \frac {h}{D_n(s)} \$, and I was wondering how you actually set \$h\$. I know that \$h\$ is chosen to so that:
\$ \frac{V_0}{V_{in}} = 1 \$ for \...
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Finding poles and zeroes for circuit driven by current source
I saw this post recently.
I had a query regarding question 1 and how FACTs can be used in the case of current source driving a circuit:
First, I set the current source to zero which is an open ...
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First order system transfer function
Suppose we have the transfer function written in the picture. The circuit from which this transfer function was derived is a classic RC circuit with an Rload (Rload parallel to the capacitor).
I have ...
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Analog Compensator Vs digital Compensator in Power electronics Converter
I was working on designing a feedback compensator for my buck converter. I decided to use the compensator circuit in the feedback and give its output to Arduino which gives the duty cycle as shown ...
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Passive filter design from transfer function
I would like to implement a passive RIAA filter circuit. This is the bode plot of a RIAA equalizer.
The transfer function of this:
H(jw) = (jwT1 + 1)/[(jwT2 + 1)(jwT3 + 1)] where time constants are ...
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What exactly changes at closed loop transfer function, when circuit move from CCM to DCM - half bridge convertor (Buck derived)
I have hard time to understand what exactly changes in close loop transfer function when it goes from ccm to dcm.
When we close loop, blocks which signals goes through are:
A(s) LC post filter with ...
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Transfer function mesh analysis
I am stuck with this problem. I simplified my answers using Mathway, and the answer in the book is different. Any help will be appreciated.
My solution:
I also don't understand how the book is able ...
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Determine the transfer function for the Butterworth bandpass filter? (At the Transfer Function Factoring and Sp Substitution stage)
The Parameter
$$a_{pass} = - 1dB$$
$$a_{stop} = - 20dB$$
$$f_{pass1} = 10kHz$$
$$f_{pass2} = 30kHz$$
$$f_{stop1} = 5kHz$$
$$f_{stop2} = 60kHz$$
A. Approximate Low Pass Filter
Filter Ordo
$$n_B = 4.29$...
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What is minimum gain crossover frequency in bode analysis?
I know gain crossover frequency at which magnitude of open loop transfer function is 0. But what is the case here for minimum Wgc?
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Calculate the transfer function of an OPAMP circuit [closed]
I have an OPAMP circuit that its output increase steadily without cahnge in the input. I guess the issue is in the transfer function of the circuit and its stability.
I want to calculate the transfer ...
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How to determine the transfer function of this pi filter?
I have this pi filter, I wonder how do i determine the dynamic model and the transfer function of this filter?
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Determining Transfer Function from Block Diagram
I'm doing my homework and need to find a transfer function W_eg (from input g to output e) using given block diagram.
The problem is that the output e disappeared.
I made a step by step solution how I ...
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Finding transfer function of high-pass circuit
I've already done the calculations myself, but I am getting a completely wrong answer for the poles and zeros. I'm not sure what I am doing wrong. If someone could point out my mistake please I would ...
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How to separate 4th order transfer function (Butterworth Approximation) into 2nd order using Python Control Library?
Previously I had the following coefficients in the program. In this program I want to create a transfer function of butterworth approximation (Digital Filter Design - Digital Signal Processing).
...
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Complex Block Diagram Reduction
I have this Block Diagram and I need to simply it. But I'm still confused and this is my progress currently. I don't know is this correct or not. Maybe someone can help me.
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Consider the following circuit system (RLC Circuit, R and L parallel then series with C), please determine the transfer function
i'm trying to figure this out, but i'm still confused. Can anyone help me? Thank you
This is what i've done. Am i in the correct path?
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Second-order RLC transfer function
I solved the exercise in the picture with Laplace:
Not being familiar with systems theory yet, I do not understand one thing (circled in pink in the picture.)
The transfer function found with the ...
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Find a model with transfer function and real data
I am currently trying to create a model using a transfer function and my data. Here is my schematic:
Here is my transfer function:
My input signal is 2.5V for 10s, after which I decrease the voltage ...
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Transimpedance amplifier with parallel RC
Consider this circuit.
Since a constant current source is present, the output voltage will always be $$V_o=i_sR_f$$
However, you can also drive $$i_s=i_c+i_R=C\frac{dv_c}{dt}+v_c/R$$
Then you can say ...
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Poles of system seem counter intuitive
I have a system with the three poles 0+8i, 0-8i, and -0.5. When I input a sinusoidal signal, this is the output:
Based on the poles, -0.5 is in the left side of the plane so it should be stable. +8i ...
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Clarification of the loop response of a TPS54350 buck converter (LTspice)
I've modeled the equivalent model for the TPS54350 shown on page 14, Figure 23, using component values from application circuit on page 15, Figure 24.
I'm feeling quite rusty on my controls knowledge ...
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How can a power converter small signal model predict transient behaviour during a load step which is a large signal disturbance?
I see small signal model being used to predict the Overshoot/Undershoot of output voltage due to a load step.
How do we justify this approach, since the basic assumption of small signal modelling is ...
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Time constants to include in Transfer function derivation of third-order filter using the FACTs method
Concerning the problem of calculating the transfer function of a third-order filter; see Help deriving the transfer function of an LC circuit?
A method kindly explained by Verbal Kint is 'FACTs', ...
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Why does my MATLAB calculation/simulation differ greatly from my LTspice simulation?
Here is my circuit in LTspice.
The frequency AC is here:
This is DC with .op command.
--- MOSFET Transistors ---
Name: m1
Model: nmos-sh
Id: ...
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Transfer functions to determine voltage of a similar circuit
Goal is to solve for the voltage u2(t)
I'm somewhat confused by this. I solved the transfer function Z(s) earlier in the top circuit, which is simply just Z. The voltage across Z in the top circuit is ...
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How do I derive a transfer function of RC circuit including ESR?
I am reading through some lecture and wondering how to derive transfer function when input source is a current source. Can you anyone give me an advice? Thank you
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Obtaining transfer function
In the above circuit j(t)=u(t)A, where u(t) is the step function. Z is a component/circuit system with no independent variables and all initial values zero. The goal is to find the transfer function Z(...
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How to find poles and zeroes in this kind of transfer function?
How do I find poles and zeroes from this complex transfer function?
$$
H(s)
= \frac{2959}{100\,s}
- \frac{ 171\, \Gamma\left( \frac{7447}{10000} \right)}
{200\, s^{7447/10000}}
$$
I used the ...
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