A diode is a two-terminal device and one of the active device in the electronic devices. It is basic and simple to understand. Most of the diodes are made up of n-type and p-type semiconductor.
Before dipping into Zener diode let us define some parameters for a diode
Zener diode is a special purpose diode that is made to operate in the breakdown region. Zener diode when used in reverse biased, it shows a sharp increase in reverse current when the voltage crosses the breakdown voltage and it is doesn't burns out.
Every diode has a reverse breakdown voltage and it depends on the doping of the impurity atom. General-purpose diode and Zener diode are much similar except the breakdown region. Let us consider a V-I characteristic of a Zener diode.
In diode forward voltage, the diode is similar to the general-purpose diode. It has forward voltage sometimes called voltage drop across the diode.
In reverse voltage the diode act as open circuit before the diode breakdown voltage.
Zener diode is useful when it is used in reverse biased. First, identify the breakdown voltage of the diode by reading the datasheet of the diode carefully. Here are some uses of Zener diode.
The Zener diode can be used to regulate voltage as it's voltage remains almost unchanged when it is operating in breakdown region.
If peak voltage is exceeding the desired voltage then Zener diode can be use to clip off the undesired voltage.
Most of the Electronics devices can be damage because of voltage spike. By using Zener diode, the voltage spike is suppressed.