Question

Question 5: Figure 5 shows a feedback trans-conductance amplifier implemented using an op amp with open-loop gain µ, a very large input resistance, and an output resistance r.. The output

current I that is delivered to the load resistance RL is sensed by the feedback network composed of the three resistances RM, R¹, and R2, and a proportional voltage Vf is fed back to the negative input terminal of the op amp. a) Find the expression for A, = 1/V₂. b) If the loop gain is large, find an approximate expression for A, and state the condition for which this applies.

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Fig: 5