Zener Diode

Zener diodes are special types of diodes that are intended for use in the breakdown region. A normal diode has a large reverse breakdown voltage. But a zener diode has a relatively smaller breakdown voltage also called as Zener voltage. A zener diode conducts current heavily at this reverse breakdown voltage. For this reason, a zener diode is usually connected in reverse position (relative to a normal diode) in electronic circuits. The usual application of a zener diode is for voltage regulation because the zener diodes offer a wide range of zener voltages that could match the voltage of regulation.Six main operating characteristics of a zener diode are: Zener Voltage, Zener impedance, Leakage current, Temperature coefficient, Diode capacitance, and Forward voltage. The zener voltage (reverse breakdown voltage) is the voltage wherein a zener diode conducts current when positioned in reverse direction. Depending on the part number, zener voltage ranges from a few volts up to hundreds of volts. The zener impendance is the effective impedance of the diode when operating in reverse breakdown voltage (zener voltage).Leakage current is the amount of current conducted by the diode when the magnitude of the voltage across the diode is less than the zener voltage. Temperature coefficient is the variation on the zener voltage due to the changes in the temperature of the diode. Diode capacitance is the effective capacitance of the diode due to the non-idealities of a diode. Lastly, forward voltage is the operating voltage wherein the diode would conduct current in the forward direction.