P N JUNCTION DIODES WORKING PRINCIPLE AND APPLICATIONS











What is a P-N Junction DIODE?


A Diode is a unidirectional device permitting the easy current flow in one direction but resisting the flow in opposite direction. A semiconductor diode is simply a P-N junction with connecting leads or terminals on its two sides. P-N junction is also called the crystal diode because it is grown out of crystal. A P-N junction may get open circuited or short circuited and the best instrument for testing a P-N junction is an ohmmeter. An ideal P-N junction diode is a two terminal polarity sensitive device that offers zero resistance, when it is forward biased and infinite resistance if reverse biased. So the diode conducts only in forward biasing condition.


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