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GATE 2020 IN – Question 49

Analog Electronics · Operational amplifiers and applications: Ideal and practical op-amps, adder, subtractor, integrator, differentiator, difference and instrumentation amplifiers, precision rectifier, active filters, comparators, Schmitt trigger · 2 marks · Numerical answer

In the shown circuit both op-amps are ideal and Vₓ = 0.5 mV. Find the steady-state output Vₒ in V, to two decimal places.

Diagram for GATE 2020 IN question 49

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Correct answer: 0.45 to 0.55

Explanation

At steady state the integrator output is constant, so its input current and the preceding amplifier output must be zero. The feedback loop therefore nulls the first amplifier’s differential input. The 99.9 kΩ/100 Ω divider feeds back $V_o/1000$ against Vₓ, giving $V_o/1000=0.5$ mV. Thus Vₒ = 0.50 V. The capacitor controls settling dynamics but not this final null condition.

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