Question

A certain $p-n$ junction, having a depletion region of width $20\mu \text{m},$ was found to have a breakdown voltage of $100\text{V}.$ If the width of the depletion region is reduced to $1\mu \text{m},$ during its production, then it can be used as a Zener diode for voltage regulation of

• A. $5\text{V}$
• B. $10\text{V}$
• C. $7.5\text{V}$
• D. $2000\text{V}$

Answer 1

The correct option is A $5\text{V}$

As,

$\text{Break down voltage}\propto \text{width of depletion region}$

$V\propto t$

$\frac{V_1}{V_2}=\frac{t_1}{t_2}$

$\frac{100}{V_2}=\frac{20}{1}$

$\therefore V_2=5\text{V}$

Thus, new breakdown voltage is $5\text{V}$.

Hence, $\left(\text{A}\right)$ is the correct answer.