A Zener diode is a specially designed, highly doped PN junction diode. The primary implementation this type of diodes can be seen as voltage regulator, Over voltage protector, as voltage reference. Zener diodes work exactly like a standard diode, with the exception of one thing. When a PN junction diode is reverse biased, the depletion layer becomes wider. This is called an avalanche breakdown. Learn how your comment data is processed. A p-n junction is created by delivering p-type semiconductor content in contact with the n-type semiconductor content and they are recognized with regards to its depletion region. 3.) the breakdown is said to have occurred due to the Zener effect.to avoid damage of diode due to excessive heating a resistor should be connected in series with the Zener diode.The Zener breakdown voltage also depends on the temperature of junction if the junction temperature increases then the Zener breakdown voltage decreases.The v-i characteristic is very sharp after the breakdown has occurred. We will learn how this takes place. The Zener voltage of diode may get altered in the course of manufacturing by using necessary and appropriate doping. As shown in the graphTo understand the working of Zener diode let’s first understandwhat is Zener breakdown? It is driven with a current source. The earlier mentioned diagram exhibits the V-I attributes of a zener diode. There is another type of breakdown in depletion layer which is sharper compared to avalanche breakdown, and this is called Zener breakdown. when Voltage across Zener diode is increased above its reverse breakdown voltage it starts conducting and reduces Voltage across it by acting short-circuited. (Supervisory Control and Data Acquisition), Programmable Logic Controllers (PLCs): Basics, Types & Applications, Diode: Definition, Symbol, and Types of Diodes, Thermistor: Definition, Uses & How They Work, Half Wave Rectifier Circuit Diagram & Working Principle, Lenz’s Law of Electromagnetic Induction: Definition & Formula. Simultaneously, you will see continuous reverse saturation current as a result of minority carriers. In the breakdown region, Zener diode works as a Voltage regulator by adjusting current flowing through it when Voltage across it becomes greater than breakdown voltage Vz. Biasing of Zener diode is as shown in the figurea.) Zener Diode Working Principle In the reverse biased condition, the diode’s depletion layer gets broad and upon enhancement of voltage levels, the layer extremely wider. Forward characteristicsForward characteristics of PN junction diode is similar to a conventional PN junction diode.2.) The earlier mentioned diagram exhibits the V-I attributes of a zener diode. Any increase in Zener Voltage will result in an increase in reverse Zener current. Typically the current must not go beyond standard valve, however in case on account of any error in the circuit the current surpasses the absolute maximum permitted limit, the device of the program could get destroyed permanently. The supply voltage Vs is always greater than the Zener voltage Vz. That is why we use a Zener diode mainly for controlling voltage in different circuits. A diode connected in reverse bias position in a circuit is shown below, Zener Diode is nothing but a single diode connected in a reverse bias, we have already stated that. For this reason slimmer depletion layer, voltage gradient or electric field strength throughout the depletion layer is fairly large. What are passive components? Free electrons with sufficient kinetic energy collide with stationary ions of the depletion layer and knock out more free electrons. To operate the zener diode in its breakdown condition, the zener diode is reverse biased by connecting its cathode to the positive terminal of the input supply. Whenever a PN junction is diode is extremely doped, the quantity of impurity atoms is going to be rich in the crystal. That means a large majority current flows through the device when the forward potential is applied to it. After certain reverse voltage across the junction, the minority carriers get sufficient kinetic energy due to the strong electric field. Eventhough at that situation current through the diode could be of any value based on the load associated with the diode. Because of this extremely heightened electric field, some of the covalent bonds in the p-n junction break-off liberating their valence electrons.