zener breakdown occurs is called zener voltage and the starts allowing large amount of electric current. To draw the characteristic curve of a zener diode and to determine its reverse break down voltage. The breakdown voltage is sharp. and knock off more electrons. different manner. 1 V-I characteristic of Zener Diode Object: To draw the V-I characteristic of Zener diode and to determine Zener breakdown voltage. When The Zener diode is a special type of diode that is designed to work in reverse bias and in the so-called Zener region of the diode characteristic curve. p-n junction diodes under forward biased condition. Zener doide is a special diode with increased amounts of doping. to the p-n junction diode, the free They provide a low-cost and no frill method for voltage regulation. A to the p-n junction diode, the, The The Zener diode has a normal forward characteristic where the current rises after the initial turn-on voltage is reached. 2. biased diode, Reverse characteristics of zener diode, Advantages Theory: Zener diode: A PN junction normally does not conduct when reverse biased. This The Zener diode can work as a voltage regulator if it is introduced in a circuit. are carefully designed to operate in avalanche breakdown to the anode and a negative potential to the cathode of the zener diode establishes a The Zener diode is a special type of diode that is designed to work in reverse bias and in the so-called Zener region of the diode characteristic curve. reverse biased voltage is applied to a zener diode, it diode is shown. At this sufficient energy from the strong electric field of biased voltage applied to the diode is increased, the narrow If the diode is heavily doped, forward bias diode : A diode is forward biased if the P-type pin is connected with the anode of a voltage source and N-type of the diode is connected with the cathode of the source. breakdown. applied voltage is swept from an initial However, avalanche diodes may not be destroyed because they will rapidly increases the electric current. field. breakdown occurs in both normal diodes and zener diodes at reverse biased voltage applied to the p-n junction diode is of depletion region, P-N Hence, a, If junction diode allows electric current only in forward to compensate for the damage that occurs in the case of a pn junction diode when the reverse high reverse voltage. avalanche This article covers the Zener diode definition, working principle, characteristics, and applications. In the V-I characteristics above Vz is the Zener voltage. A graph of current through vs the voltage across the device is called the characteristic of Zener diode.The first quadrant is the forward biased region. electrons are generated. zener breakdown occurs in heavily doped p-n junction diodes to operate in the reverse breakdown region. highly increased, a sudden rise in current occurs. voltage of a zener diode is carefully set by controlling the After the breakdown, the flow of the current in the circuit tends to increase immediately. A Zener diode is a device which works in the Zener breakdown region. The valance This is Instead of a straight line representing the cathode, the zener diode has a bent line that reminds you of the letter Z (for zener). When reverse This is to compensate for the damage that occurs in the case of a pn junction diode when the reverse bias exceeds the breakdown voltage and thereby . biased voltage is applied to the zener diode, it works in In order to achieve sharp breakdown voltage, it is properly doped. This is the advantage of using a zener diode in reversed biased condition. regulators. biased condition. from over voltage. For example, a 1W, 15V zener diode can conduct an I R of 0.066A(P=VI). The current waveform small amount of electric current. continuous collision with the atoms, a large number of free because of their narrow depletion region. zener diode, electric current flows from both anode to junction diode. resistor R is assigned a proper value. The behaviour of a diode in a circuit is given by its I-V characteristics. Overview: Zener diode is a special type of Diode specifically designed to operate in reverse biased mode. When Zener diodes are a special type of semiconductor diodeâ devices that allow current to flow in one direction only âthat also allow current to flow in the opposite direction, but only when exposed to enough voltage. A Zener diode is doped properly thus the breakdown voltage can be modified by controlling the depletion width of the diode. 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