What is zeren diode?

Answer 1

A normal diode only allows current to flow in one direction, e.g: A to B. However, current will only flow across this diode A to B when there is a voltage ( called the breakdown voltage), and different normal diodes require different voltages to allow current to flow, e.g: silicon diodes allow current to flow A to B when there is a minimum of 0.6V flowing, at which point the resistance drops, and current flows.

A zener diode does exactly this, however, it also allows current to flow in an opposite direction once the breakdown voltage for this direction has been reached. e.g: if a Zener diode has a breakdown voltage of 3.6V, at 3.6V its resistance will drop significantly enough so that current can flow.

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