What is a Zener Diode?

What is a Zener Diode?

Zener diodeis also called as a breakdown Diodes, are widely used as voltage references and as shunt regulators to regulate the voltage across small circuits.

It’s silicone-based discrete semiconductor devices which allow current to flow bidirectionally - either reverse or forward. Diodes are comprised of a heavily-doped P-N silicone junction, which is intended to conduct in the reverse direction once a particular voltage threshold has been met. Zener diodes are the most common electronic components used as stable voltage references for electronic circuits.

Zener diode have a set reverse breakdown voltage. When this is reached, they start to conduct current and continue to operate unceasingly in the reverse bias direction without incurring damage. One of the main benefits of Zener diode is that a varying range of voltages will still maintain a constant voltage drop across the Diodes. As a result, Zener diodes can be used for voltage regulation applications.

Current going across the terminals in reverse bias (backward) is called the Zener effect. 

Voltage tolerance of a Zener diode is typically ±5%

There are two types of breakdowns for a Zener diode:

• Avalanche      Breakdown

• Zener Breakdown

Clarence Melvin Zener was the first person to describe the electrical properties of the Zener diode.

The major difference between a Zener diode and a normal diode lies in the passage of current. A normal diode allows current to flow only in one direction, while Zener diode allows current to flow in both directions.