JEE PYQ: Semiconductors Question 31
Question 31 - 2019 (09 Apr 2019 Shift 1)
An NPN transistor is used in common emitter configuration as an amplifier with $1\ \text{k}\Omega$ load resistance. Signal voltage of 10 mV is applied across the base-emitter. This produces a 3 mA change in the collector current and 15 $\mu$A change in the base current. The input resistance and voltage gain are:
(1) $0.33\ \text{k}\Omega$, 1.5
(2) $0.67\ \text{k}\Omega$, 300
(3) $0.67\ \text{k}\Omega$, 200
(4) $0.33\ \text{k}\Omega$, 300
Show Answer
Answer: (2)
Solution
$R_i = 10 \times 10^{-3}/(15 \times 10^{-6}) = 0.67\ \text{k}\Omega$. Voltage gain $= (3 \times 10^{-3})/(15 \times 10^{-6}) \times 1000/670 = 300$.
BETA
