The I–V characteristics of a p-n junction diode in forward bias is shown in the figure. The ratio of dynamic resistance, corresponding to forward bias voltage of 2 V and 4 V respectively, is
- 1:2
- 5:1
- 1:40
- 20:1
The Correct Option is B
Solution and Explanation
Dynamic resistance
\(=\)\(\frac{dV}{dl}\)
\(⇒\) \(r_1 = \frac{2.1 - 2 \, \text{k}\Omega}{10^{-5}}\)
and \(r_2 = \frac{4.2 - 4 \, \text{k}\Omega}{250 - 200}\)
\(⇒ \)\(r1 :r2 = 5 : 1.\)
So,Correct option is (B)
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Concepts Used:
P-n Junction
A P-N junction is an interface or a boundary between two semiconductor material types, namely the p-type and the n-type, inside a semiconductor.
Biasing conditions for the p-n Junction Diode:
in p-n junction diode two operating regions are there:
- P-type
- N-type
There are three biasing conditions for p-n junction diode are as follows:
- Zero bias: When there is no external voltage applied to the p-n junction diode.
- Forward bias: P-type is connected to positive terminal of the voltage potential while n-type is connected to the negative terminal.
- Reverse bias: P-type is connected to negative terminal of the voltage potential while n-type is connected to the positive terminal.