What's the feedback for an op amp?

In summary, negative feedback is used in op amps to improve bandwidth, linearity, and stability. It involves sending a portion of the amplified output signal back to the input, resulting in a subtraction of the two signals. This also reduces the sensitivity to uncertainties and tolerances in the circuit. The formula for finding the frequency in an op amp is the same as the input frequency since negative feedback does not affect it.
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Alaguraja
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What's the feedback for an op amp? And tell me the formula.
 
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Thank you for this video. And I need formula to find the frequency.
 
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Alaguraja said:
And I need formula to find the frequency.

what frequency ?
 
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The output wave's frequency.
 
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Alaguraja said:
The output wave's frequency.

it's going to be the same as the input, why do you think it would change ?

consider ... if I am using an op-amp as a microphone preamplifier, the last thing I am likely to want is the frequency to be changingDave
 
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Alaguraja said:
What's the feedback for an op amp? And tell me the formula.

When applying feedback to an amplifier, we send a certain part of the amplified output signal back to the input - and superimpose both parts (input and feedback signal).
In most cases, we make use of NEGATIVE feedback where the feedback signal is substracted from the input. This method has many advantages: Bandwidth increase, linearity improvement, gain reduction with reduced sensitivity of the gain value against uncertainties and tolerances of the active element.

However - as everything in electronics is a trade-off between conflicting requirements - negative feedback has one disadvantage: The stability of the circuit against unwanted oscillations (self-excitement) is reduced. With other words: The stability margin is reduced.
 
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1. What is an op amp?

An op amp, short for operational amplifier, is an electronic circuit component that amplifies the difference between two input signals and outputs a corresponding amplified signal.

2. How does an op amp work?

Op amps work by using an external power supply to amplify the voltage difference between the two input terminals. This amplified voltage is then output to a load or another circuit component.

3. What is feedback in an op amp?

In an op amp, feedback is a mechanism used to control and adjust the output signal. It involves connecting a portion of the output signal back to the input terminals, which can affect the amplification process.

4. Why is feedback important in op amps?

Feedback is important in op amps because it allows for stability and precision in the amplification process. It helps to reduce distortion and noise, and allows for more control over the output signal.

5. How do you calculate feedback in an op amp?

The most common way to calculate feedback in an op amp is by using the feedback resistor formula, which is Vout/Vin = -Rf/Rin. This formula takes into account the feedback resistor (Rf) and the input resistor (Rin) to determine the overall feedback of the op amp circuit.

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