CT-4_Feedback Amplifiers-Rollno-451-LE7

Open-loop gain of an amplifier is given by:

• A

• Aβ

• β

• None of the above

The input impedance of an amplifier can be increased from 2 kilo ohm 250 Kohm by introducing

• Shunt current negative feedback

• Shunt voltage negative feedback

• Series current negative feedback

• None of these

If both input and output is voltage then the amplifier is called ________

• Voltage amplifier

• Current amplifier

• Trans conductance

• Trans resistance

The shunt driven (output) series fed (input) also called _____________ series

• Current

• Voltage

• Both a and b

• None of the above

If the open loop gain of an amplifier is 100, when negative feedback with beta=0.04 is introduced, it's been will be gain of an amplifier with feedback

• 20

• 25

• 4

• 0.4

For a shunt-shunt negative feedback amplifier

• Input impedance decreases but output impedance increases

• Both input impedance and output impedance increases

• Both input impedance and output impedance decreases

• None of the above

In a feedback amplifier, sensitivity D is equal to:

• Aβ

• 1 - Aβ

• 1 + Aβ

• 1/(Aβ + 1)

In series -series connection the forward-path gain is __________

• Voltage gain

• Current gain

• Transconductance

• Transimpedance

In a negative feedback amplifier, shunt mixing:

• Tends to increase the input resistance

• Tends to decrease the input resistance

• Does not alter the input resistance

• Produces the same effect on input resistance as the series mixing

In a negative feedback amplifier, voltage sampling:

• Tends to decrease the output resistance

• Tends to increase to output resistance

• Does not alter the output resistance

• Produces the same effect on output resistance as current sampling