JEE Main20198 Apr 2019Evening ShiftPhysicsSemiconductorsActual
A common emitter amplifier circuit, built using an NPN transistor, is shown in the figure. Its dc current gain is 250 , R C = 1 kΩ and V C C = 10 V . The minimum base current for V C E to reach saturation is
Options
- A10 μ A
- B40 μ A
- C7 μ A
- D100 μ A
Correct answer
B. 40 μ A
Step-by-step solution
Given, β = 250 R C = 1000   Ω V C C = 10   V At saturation, V C E = 0 ⇒ i e = 10   V 1000   Ω = 10   m A Current gain factor, β = i e i B ⇒ i B = i e β = 10   m A 250 = 40   μ A