Question: What is the main characteristic of a Zener diode?

Options:

1. It can amplify signals
2. It allows current to flow in both directions
3. It maintains a constant voltage across it
4. It is used for switching applications

Correct Answer: It maintains a constant voltage across it

Solution:

Zener diodes are designed to maintain a constant voltage across them when reverse-biased, making them useful for voltage regulation.