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GATE 2025 EE – Question 39

Analog and Digital Electronics · Simple diode circuits: clipping, clamping, rectifiers · 2 marks · Multiple choice

In the circuit shown below, if the values of R and C are very large, the form of the output voltage for a very high frequency square wave input, is best represented by

Diagram for GATE 2025 EE question 39
  1. Plot (A)
  2. Plot (B)
  3. Plot (C)
  4. Plot (D)

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Show answer and explanation

Correct answer: (C) Plot (C)

Explanation

For a very large time constant $RC$ compared with the period of the input, the RC network acts as an integrator. The output is the integral of the square wave: a triangular wave (slightly curved because of the exponentials) with a very small amplitude centred on zero, much smaller than the ±1 V input. That is plot (C); plot (A) would need a triangle as large as the input, and plot (B) is an unfiltered square wave.