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प्रश्न
State its any ‘two’ uses of photodiode.
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उत्तर
Uses Of Photodiode:-
i. Photodiode is used in optocouplers which are used to couple isolated circuits.
ii. Photodiodes are widely used to detect optical signals.
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संबंधित प्रश्न
With the help of a neat circuit diagram, explain the working of a photodiode.
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- its forward bias
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- its size
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LED is a heavily doped P-N junction which under forward bias emits spontaneous radiation. When it is forward-biased, due to recombination of holes and electrons at the junction, energy is released in the form of photons. In the case of Si and Ge diode, the energy released in recombination lies in the infrared region. LEDs that can emit red, yellow, orange, green and blue light are commercially available. The semiconductor used for fabrication of visible LEDs must at least have a band gap of 1.8 eV. The compound semiconductor Gallium Arsenide – Phosphide is used for making LEDs of different colours.
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OR
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