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An op-amp based programmable gain amplifier with a negative feedback is designed. Which method will be the best suitable for the stability analysis?

An op-amp based programmable gain amplifier with a negative feedback is designed. Which method will be the best suitable for the stability analysis? Correct Answer Bode Plot

Concept-

Stability can be determined easily from a plot of the loop gain versus frequency.

The critical point is when the loop gain equals 0 dB (gain equals 1) because a circuit must have gain ≥ 1 to become unstable.

The phase margin, which is the difference between the measured phase angle and 180º, is calculated at the 0-dB point.

Bode plot is the plot of loop gain versus frequency.

Using Bode Plot we can easily find the gain margin and phase margin of the system.

We can also see the effect of resistor or capacitance on the Bode plot by analyzing the Bode plot.

We can get different parameters like Bandwidth, the cutoff frequency of op-amp by bode plot So the Bode plot is the best suitable for stability analysis.

Related Questions

Consider the following statements with respect to the feedback from the control systems: 1. The feedback can improve stability or be harmful to stability if it is not properly applied. 2. The feedback can always improve stability. 3. In many situations, the feedback can reduce the effect of noise and disturbance on system performance. 4. In general, the sensitivity of the system gain of a feedback system of a parameter variation depends on where the parameter is located. Select the correct statements.
Consider the following statements with respect to the feedback of the control systems. i. Feedback can improve stability or be harmful to stability if it is not properly applied. ii. Feedback can always improve stability iii. In many situations the feedback can reduce the effect of noise and disturbance on system performance. iv. In general the sensitivity of the system gain of a feedback system of a parameter variation depends on where the parameter is located.
Consider the following statements with respect to the feedback of the control systems: 1. Feedback can improve stability or be harmful to stability if it is not properly applied. 2. Feedback can always improve stability 3. In many situations the feedback can reduce the effect of noise and disturbance on system performance. 4. In general the sensitivity of the system gain of a feedback system of a parameter variation depends on where the parameter is located.
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