Zener Diode

What is Zener diode in physics? How does a zener diode work? Why zener diode is used as a voltage regulator?


Zener diode

A scientist Zener invented the properties of Zener diode that’s why it is named after him. It is nothing but a simple diode connecting in reverse bias. So the Zener diode is a PN junction diode which flow current in the forward direction similarly to the conventional PN junction diode but in the reverse biased it also permits flow of current (dramatic increase in current) when the applied voltage reached at above a certain value; This value of voltage is known as the Zener knee voltage or Zener breakdown voltage, or peak inverse voltage.

The electron quantum tunneling under high electric field strength is responsible for the reverse breakdown effect and this effect is known as the Zener effect.

Zener Diode

Application of Zener Diode

The constant reverse voltage of a Zener diode renders it a very useful component in regulating the output voltage against variations in the Input voltage or load resistance from an unregulated power supply. The current through the Zener diode will change in order to keep the voltage within the threshold limits of Zener action and the maximum power that it can dissipate.

With the help of these types of properties we can use Zener diode as:

Voltage regulator, peak clippers, switching operations, reference elements,  Over voltage protector, as voltage reference, surge suppressors for device protection, and in meter protection etc.