Semiconducting Devices Question 43
Question: The junction diode in the following circuit requires a minimum current of 1 mA to be above the knee point (0.7 V) of its I-V characteristic curve. The voltage across the diode is independent of current above the knee point. If VB = 5 V, then the maximum value of R so that the voltage is above the knee point, will be
Options:
A) 4.3 kW
B) 860 kW
C) 4.3 W
D) 860 W
Show Answer
Answer:
Correct Answer: A
Solution:
At knee point voltage across the diode is 0.7V.
Hence voltage across resistance R is 5 - 0.7 = 4.3 V.
Therefore using V = iR
Therefore 4.3 = 1 x 10-3 x R
Therefore R = 4.3 kW.
