In the following limiter circuit, an input voltage Vi =

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In the following limiter circuit, an input voltage V_i = 10 sin 100 πt is applied. Assume that the diode drop is 0·7 V when it is forward biased. The Zener breakdown voltage is 6·8 V.
The maximum and minimum values of the output voltage respectively are—

1. 6·1 V, – 0·7 V
2. 0·7 V, – 7·5 V
3. 7·5 V, – 0·7 V
4. 7·5 V, – 7·5 V

Correct Option: C

The given circuit (i.e., fig - 1)
Given V_D1 = V_D2 = 0·7V and V_Z = 6·8V
For first half cycle equivalent circuit of the given circuit is shown below (i.e., fig - 2)
From above circuit V₀ = 0·7 + 6·8 = 7·5V
For second half cycle the equivalent circuit is shown below: (i.e., fig - 3)
From figure, V₀ = – 0·7V
Therefore maximum value of output voltage is 7·5V and minimum value of output voltage is – 0·7V.
Hence alternative (C) is the correct choice