semiconductor-electronics--materials-devices-and-simple-circuits Question 22
Question: Q. 1. (i) In the following diagram, is the junction diode forward biased or reverse biased?
U] [OD I, II, III 2017]
(ii) Draw the circuit diagram of a full wave rectifier and state how it works.
Show Answer
Solution:
Ans. (i) The nature of biasing
(ii) Diagram of full wave rectifier Working
(i) Reverse Biased
(ii) Diagram of full wave rectifier :
Working : The diode $D_{1}$ is forward biased during one half cycle and current flows through the resistor, but diode $D_{2}$ is reverse biased and hence no current flows through it. During the other half of the signal, $D_{1}$ gets reverse biased and no current passes through it, $D_{2}$ gets forward biased and current flows through it. In both half cycles current, through the resistor, flows in the same direction.
(Note : If the student just draws the following graphs (but does not draw the circuit diagram), award $1 / 2$ mark only.)
1
[CBSE Marking Scheme 2017]
Detailed Answer :
(i) The diode shown in diagram is reverse biased as in case of reverse bias $p$ junction is connected to -ve of battery and $n$ junction with positive which causes effective barrier voltage enhancement $V_{B}+V$ with high resistance.