
Describe the V-I characteristics of a photodiode.
Important Questions on Semiconductor Electronics: Materials, Devices and Simple Circuits



Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Photodiodes are used in forward bias usually for measuring the light intensity.
Reason R: For a junction diode, at applied voltage the current in the forward bias is more than the current in the reverse bias for where is the threshold voltage and is the breakdown voltage.
In the light of the above statements, choose the correct answer from the options given below






Three photo diodes and are made of semiconductors having band gaps of and , respectively. Which ones will be able to detect light of wavelength ?
Given Planck constant is ,speed of light




Match the following List-I with List-II
List I | List II | ||
A | Transistor amplifier | I | Active region |
B | Transistor switch | II | Cut-off region |
C | Zener diode | III | Voltage regulator |
D | Fermi level | IV | Average energy of charge carriers |
The correct answer is:



The value of the resistor, , needed in the DC voltage regulator circuit shown here, equals:




Two - photodiodes are fabricated from semiconductors with band gap of and respectively.
Choose the correct statement from the following.

