Question

An experiment is performed to determine the $I-V$ characteristics of a Zener diode, which has a protective resistance of $R=100\Omega$, and a maximum power of dissipation rating of $1W$. The minimum voltage range of the DC source in the circuit is

• A. $0-24V$
• B. $0-5V$
• C. $0-12V$
• D. $0-8V$

Answer 1

The correct option is A $0-24V$

The circuit diode for a zener diode with a protective resistance is shown.

Applying KVL,

$V=iR+V_D$

$V_D=V-iR=V-100i$

Maximum power dissipated across the zener diode is given by:

$P=V_{D}i=(V-100i)i=1$

$\therefore 100i^2-Vi+1\ge 0$

Current should be real, hence determinant is greater than zero.

$\therefore V^2>400$

$V>20V$