Question
The gain of common-emitter amplifier is given by AV= – gmRL. If RL is increasing indefinitely, will the gain of the amplifier also increase indefinitely? Explain.
Solution
Gain of the common-emitter amplifier is given by,
AV= – gmRL ...... (1)
No, if the load resistance is increased indefinitely, the output current will become zero. Hence, the voltage gain will be zero. Therefore, there will be 0 gain in the amplifier.
In equation (1) gm is called transconductance and is equal to current gain per unit input resistance.
AV= – gmRL ...... (1)
No, if the load resistance is increased indefinitely, the output current will become zero. Hence, the voltage gain will be zero. Therefore, there will be 0 gain in the amplifier.
In equation (1) gm is called transconductance and is equal to current gain per unit input resistance.