Question

draw a circuit diagram to expalin the working of a photodiode. also draw the V-I characteristics of this semiconductor diode​

Answer 1

Photodiode is light sensitive electronic device that converts light into voltage signal or current signal. It carries two terminals - anode and cathode showing Light rays reflection in form of photo detector. It works normally on principle of photo generation.

Working : In this, the photons hit the diode resulting in electron-hole pairs where intensity of photon absorption is based on photon energy where less In the PN junction as shown, in case of absorption in depletion region, the hole pairs are removed from the p-n junction due to inside electric field in depletion region that makes theholes to move towards anode with electrons toward cathode forming photocurrent. Here, total photocurrents and dark currents flowing with/without light is sum of current through photodiode.