Q 12-14-173JEE MainJEE Main 2020 (4 Sep, Shift 1)Medium
Take the breakdown voltage of the zener diode used in the given circuit as $6\ \text{V}$. For the input voltage shown in the figure below, the time variation of the output voltage is: (Graphs drawn are schematic and not to the scale)
Answer: (C) Graph (C)
The two zener diodes are connected back to back across the output. In each half cycle one diode is forward biased (nearly zero drop) and the other is reverse biased.
When $|V_{in}|$ exceeds $6$ V, the reverse-biased diode breaks down and holds the output at about $6$ V; below that, no current flows and $V_o = V_{in}$.
So both the positive and the negative peaks ($\pm10$ V) are clipped at about $\pm6$ V: graph (C).
Solution by Sreeraj P, M.Sc Physics