# Linear Integrated Circuit Questions and Answers – Block Diagram Representation of Feedback Configurations

This set of Linear Integrated Circuit Multiple Choice Questions & Answers (MCQs) focuses on “Block Diagram Representation of Feedback Configurations”.

1. A feedback amplifier is also called as
a) Open loop amplifier
b) Closed loop amplifier
c) Feedback network amplifier
d) Looped network amplifier

Explanation: A feedback amplifier is sometimes referred as a closed loop amplifier because the feedback forms a closed loop between input and the output.

2. How many types of configuration are available for feedback amplifier?
a) Six
b) Four
c) Two
d) Eight

Explanation: There are four type of configuration are available. They are voltage series feedback, voltage shunt feedback, Current series feedback and Current shunt feedback.

3. Which of the following is not a feedback configuration?
a) Current-series feedback
b) Voltage-shunt feedback
c) Current-Voltage feedback
d) Current-Shunt feedback

Explanation: In a feedback amplifier, either current or voltage can be fed back to the input, but both current and voltage cannot be feedback simultaneously.

4. When load current flows into the feedback circuit, the configuration is said to be
a) Current-shunt feedback
b) Voltage-shunt feedback
c) Voltage-series feedback
d) All of the mentioned

Explanation: In current-series and current-shunt feedback circuit, the load current flows into the feedback circuit.

5. Find the voltage-series feedback amplifier from the given diagram?
a) b) c) d) Explanation: The mentioned diagram is the voltage-series feedback amplifier because the voltage across load resistor is the input voltage to the feedback circuit.

6. On what criteria does the feedback amplifier are classified?
a) Signal fed back to input
b) Signal applied to input
c) Signal fed back to output
d) None of the mentioned

Explanation: The feedback amplifiers are classified according to whether the voltage or current is fed back to the input in series or in parallel.

7. The closed loop voltage gain is reciprocal of
a) Voltage gain of op-amp
b) Gain of the feedback circuit
c) Open loop voltage gain
d) None of the mentioned

Explanation: Comparing the equation of closed loop voltage gain (AF) and the gain of the feedback circuit (B). AF is reciprocal of B
=> AF = 1+( RF/ R1) ; B= R1/( R1+ RF)
=> B = 1+( R1/ RF)
Therefore, AF = 1/B.

8. Select the specifications that implies the inverting amplifier?
a) V1 = -3v, V2 = -4v
b) V1 = -2v, V2 = 3v
c) V1 = 5v, V 2 = 15v
d) V1 = 0v, V2 = 5v

Explanation: In inverting amplifier, the input is applied to the inverting terminal and the non-inverting terminal is grounded. So,the input applied to inverting amplifier can be V1 = 0v, V2 = 5v.

Sanfoundry Global Education & Learning Series – Linear Integrated Circuits. 