What is photo diode ? Briefly explain its working and draw its V-I characteristics.
A photodiode is a special type of p-n junction diode fabricated with a transparent window to allow light to fall on the diode and the generation of electron and hole pairs takes place in or near the depletion region of the diode.
Working of a photodiode:-
when the photodiode is illuminated with light of suitable frequency, then electron and holes pairs are generated near depletion region due to its specific fabrication, the junction potential separates electrons n-side and holes reaches to p-side and current flows across the photodiode when connected with the load.
The V-I graph:-