Question

For a transistor amplifier in common emitter configuration for load impedance of $1k\Omega (h_{fe}=50$ and $h_{oe}=25\mu A/V)$, the current gain is:

• A. $-5.2$
• B. $-15.7$
• C. $-24.8$
• D. $-48.78$

Answer 1

The correct option is D $-48.78$

For transistor amplifier in common emitter configuration current gain,

$A_i=\frac{-h_{fe}}{1+h_{oe}{R}_L}$

$\therefore A_i=\frac{-50}{1+25\times {10}^{-6}\times 1\times {10}^3}$

$\therefore A_i=-48.78$