Questions tagged [cutoff-frequency]

A cutoff frequency is a frequency boundary in a system's frequency response at which the power level is greater or less than a given fixed value.

82 questions
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Transfer Function / Cutoff Frequency

I am trying to get the formula for the cutoff Frequency out of this transfer function: . I think this is the transfer function: . And I get this formula for the cutoff frequeny: Calculation ...
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Variable Frequency-Response analysis (amplifier)

I'm trying to understand what the book "Basic Engineering Circuit Analysis" by Irwin is saying at the chapter of variable frequency... It's trying to amplify a signal from 50Hz to 20000Hz. Where it ...
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Why is the cutoff frequency of this highpass filter with formula different from LTspice?

I used this online tool to play around and design a Sallen-Key low pass filter with a cutoff frequency of 0.3Hz. When I now put the resulting values for R1, R2, C1 and C2 in the formula I get exactly ...
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How to determine the best resistance for a weak signal Twin-T notch filter?

I am designing a 50/60 Hz Twin-T notch filter for a weak (biomedical) signal output from an instrument amplifier (InAmp) to be chained to another active low pass ...
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Calculating cutoff frequency of a second order active filter

I'm trying to calculate cutoff frequency of the low pass filter that schematic is shown below. I obtained this circuit from Analog Filter Wizard and it's cutoff frequency is 170kHz at -3 dB, but when ...
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Regards Band Pass Filter with AmpOp

I've tried to solve this contest question regards the band pass filter (find the frequency at low-pass and high-pass filters) the picture below: My attempt: I consider that the first stage is 2 low-...
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Does a low-pass filter average the higher-order frequencies into a “DC offset”?

In a Pound-Drever-Hall lock, an electronic signal is produced of the form: We are interested in electronically isolating the term: My question is: how can we filter to get exactly this term (listed ...
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Signal Attenuation TVS and series resistor

This question is in regards to signal attenuation on high speed data lines like RS-485 (and any others as well). I'm new to the signal world, so please bear with me here. Are there some useful ...
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Common mode choke parameters CAN circuitry - split termination concept

I am trying to the understand the important parameters of a common mode choke that will be placed at the CANL and CANH lines of a transceiver. First parameter: Impedance as function of frequency - I'...
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(Lack of) Miller Effect in Cascode considering Common Emitter and Common Base Seperately

I'm currently working on an analysis of a standard Cascode circuit, in particular why the frequency response is so good as it reduces the miller effect. I have had a very vague explanation given to ...
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Skewed frequency response of RLC circuit

I built a simple RLC circuit: I'm using a signal generator as input, and I'm reading the voltage across the capacitor with an oscilloscope. I've calculated that the resonant frequency (where I will ...
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What happens to the low cut off frequency when replaced with a larger bypass capacitor?

When the emitter capacitance is increased to 100 microfarads. What would happen to the low frequency cut off of this amplifier?
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Second Order Passive RC Low Pass Filter Doesn't Have -6dB at cutoff Frequency in LTSpice

For Second-Order RC filter the cutoff frequency is: $$fc = \frac{1}{2\pi \sqrt {R_1C_1R_2C_2}}$$ I have taken R1 = R2 = R = 1K Ohm and C1 = C2 = C= 0.1591 micro Farad. So the cutoff frequency comes ...
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Simple OP-AMP Frequency Response

In my textbook, there are two interrelated equations. 1. wb = wt / (1 + R2/R1) 2. wb = wt / Ao where ...
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Behavior of frequency in a sinusoidal circuit

My question is in regards to a circuit like this with a sinusoidal voltage source Vin. When I try to figure out the voltage ratio between Vin and Vout I get ωCR/(ωCR - j). I then try to ...
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Scaling of magnetic field strength and flux density measurements and shape of hysteresis loop

Note: this is part of a larger question which I was asked to separate into subquestions. Other subquestions: 1 and 2 I'm using the method outlined here to measure the induced magnetic flux density in ...
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Cutoff frequency of passive RC integrator used to measure magnetic flux density

Note: this is part of a larger question which I was asked to separate into subquestions. Other subquestions: 1 and 2 I am using a passive RC integrator to measure the induced magnetic flux density in ...
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Cut-off frequency calculation

Can anyone calculate the cut-off frequency and tell me which formula to be used on the Positive end of OPAMP? what is the role of R1 here and R7 from the feedback? Please answer in details with ...
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i want to know the cut off frequency on the 2 OPAMPS … Do I take 6K resistor and 5K resistor for OPAMP#2

I hope some one can check, I have a signal coming from a source and it goes in to 2 OPAMPS, and both has to be checked for cutoff frequencies... I know 1/2*pi*RC is the formula but my question is how ...
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frequency response multistage

hello every one i need ask about frequency response i have an old question of our professor exam in few year, and i try to solve this question many time but i can't so please if any one have idea ...
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MOS Amplifier Circuit - Lower 3dB Frequency Calculation

I am confused with the above problem as the output node is not specified. If the output node is drain, it will be common source and if output is source, then it will be common drain. My question is ...
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Derivation of cutoff frequency and phase shift for RC low pass filter

I've been having some problems with how to find the cutoff frequency and the phase shift for a simple RC low pass filter circuit. I've read this post, but I need a better understanding of what ...
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Which cut off frequency I should use in order to cancel AC noise with the low pass filter?

it may sound a bit stupid, but the thing is that I want to cancel the noise caused by AC frequencies in a circuit. I know I have to use a low pass filter, but which cut-off frequency should I use? I'...
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Can a filter change the frequency of the input signal?

I am given a square wave with Vmin = 0V and Vmax=5V , T(period)=8ms and duty cycle 25%. I am asked to find the properties(low cutoff , high cutoff , bandwidth) of a band pass filter that will make the ...
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Calculating cutoff frequency of RCL circuit

Given is this circuit: I know that: $$G(j\omega)=\frac{\frac{1}{j\omega C}}{j\omega L+\frac{1}{j\omega C}+R}$$ But how do I calculate from this my cutoff frequency?
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Significance of cut-off frequency in a low-pass filter

My question is: why do we choose cut-off frequency to satisfy that the magnitude of transfer function $H(\omega) = \frac{1}{\sqrt{2}}$? Therefore I am not asking how cut-off frequency is ...
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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 ...
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how can I calculate the cutoff frequency for this low pass filter?

simulate this circuit – Schematic created using CircuitLab
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How is definition of cutoff frequency consistent with KVL?

Low pass and high pass $RC$ filters have a cutoff frequency that is equal to $$f_c=\frac{1}{2\pi RC}$$ This should be the frequency at which the ratio $|V_{out}/V_{in}|$ is equal to $1/\sqrt{2}$....
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Determining value of capacitor, in a opamp ampifier circuit

I am working on the follwing circuit, and have found all values for the components, except for C3 which i have a hard time finding. My requirements are that it should be able to handle 40-16k Hz with ...
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Low frequency response of a BJT amplifier.How is the cutoff frequency equal to $\frac{1}{2\pi (R_S+R_{in})C_{in}}$ in fig 2

In a low frequency region of the single stage BJT amplifier, it is the RC combinations formed by the capacitors $C_{in},C_E,C_{out}$ -Electronic Devices and Circuit Theory-Boylestad ...
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Bandpass Filter Attenuation?

I'm trying to split an audio signal into 5 channels, letting 5 different ranges through each filter (low, mids, highs, etc..). What I'm finding is that each bandpass filter has different levels of ...
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Decreasing of $V_{in}$ in a high pass filter due to the type of capacitor used

I observed a strange fact while using a simple RC high pass filter. Here is the circuit I used. On $CH1$ I measured $V_{out}$, while on $CH2$ I observed the value of $V_{in}$. I kept the ...
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Are slew rate frequency and cut off frequency same?

I am bit confused about the cut off frequency and the max frequency above which the output response starts to distort which is slew rate frequency. Are these two things same? Cutoff frequency (f) = ...
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Divider and lowpass combined

I am using the following circuit for two purposes: As a voltage divider, to reduce DC sensor output to a range suitable for my ADC. As a lowpass filter, to remove high frequency noise from the signal....
Can anyone guide me through how to hand draw a correct Bode magnitude plot for $$G(s) = \dfrac{48000}{s(s+0.1)(s+100)}$$ Don't even need phase plot, just need correct magnitude plot As few ...