The GATE Grind

GATE 2021 IN – Question 57

Analog Electronics · Operational amplifiers and applications · 2 marks · Numerical answer

For the shown ideal OPAMP circuit, output Vo is ______ V (one decimal place).

Diagram for GATE 2021 IN question 57

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: 1.0 to 1.1

Explanation

Negative feedback gives V−=V+=0.05 V. Let the centre of the T network be Vx. KCL at V− gives (0.05−Vx)/10k+0.05/12k=0, so Vx=0.0916667 V. KCL at Vx gives (Vx−0.05)/10k+Vx/1k+(Vx−Vo)/10k=0, hence Vo=12Vx−0.05=1.05 V, rounded to one decimal **1.1 V**.