The gain of a common emitter amplifier is given by `A_(V)=-g_(m)R_(L)` – InterviewSolution

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1.	The gain of a common emitter amplifier is given by `A_(V)=-g_(m)R_(L)`. Does it mean that if we keep on increasing indefinitely `R_(L)`, the gain of the amplifier will also increase indefinitely? Explain your answer.
Answer» The gain of the amplifier will not increase indefinitely on increasing `R_(L)` indefinitely. As `V_C=V_(CE)-I_C R_(L)` Therefore, as `R_(L)` increases, the value of `V_C` decreases. When the value of `V_C` becomes less than the base voltage, both the junction in transistor get forward biased. Due to it, the current becomes saturated. It means no further increase of current takes place and hence no further gain of the amplifier.

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