A Zener diode allows current to flow in reverse once the Zener voltage is reached, unlike regular diodes. In forward bias, it behaves like a typical diode, with a threshold voltage around 0.7V. In reverse bias, once the Zener voltage is reached, the voltage remains nearly constant, and the current increases rapidly, which is used for voltage regulation.

Significance

• Voltage regulation in power supplies.

• Clipping circuits to protect components from voltage spikes.

• Reverse voltage protection.