Silicon Avalanche Diode

An avalanche diode is a diode (usually made from silicon, but can be made from another semiconductor) that is designed to break down and conduct at a specified reverse bias voltage. The Zener diode exhibits an apparently similar effect, but its operation is caused by a different mechanism, called Zener breakdown. Both effects are actually present in any such diode, but one usually dominates the other. Zener diodes are typically restricted to a few tens of volts maximum, but silicon avalanche diodes are available with breakdown voltages of over 4000 V.[1]
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