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Diode

Frederick Guthrie invented the diode in 1873, but did not put it into practical use. Thomas Edison independently developed it in 1880, then used it in his 1883 patent of the incandescent light bulb. John Ambrose Fleming received the first patent on the diode itself in 1904.

A Diode is a two terminal active component that conducts primarily in one direction.

Diodes are one of the simplest, but most useful of all semiconductor devices. Many types of diode are used for a wide range of applications. Rectifier diodes are a vital component in power supplies where they are used to convert AC mains (line) voltage to DC. Zener diodes are used for voltage stabilization, preventing unwanted variations in DC supplies within a circuit.

Signal diodes are used to obtain the audio and video signals from transmitted radio frequency signals (demodulation) and can also be used to shape and modify AC signal waveforms (clipping, limiting and DC restoration). Diodes are also built into many digital integrated circuits to protect them from dangerously large voltage spikes.

Types of diodes :

P-N junction diode


Zener diode


Shocttky diode


Led


Photodiode


Tunnel diode


Variable capacitor diode

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