# Feedback Amplifiers

 Question 1
In the circuit shown below, $V_{1}$ and $V_{2}$ are bias voltages. Based on input and output impedances, the circuit behaves as a

 A voltage controlled voltage source. B voltage controlled current source. C current controlled voltage source. D current controlled current source.
GATE EC 2023   Analog Circuits
Question 1 Explanation:

Here from circuit,
$M_{1}$ is common-gate amplifier and $M_{2}$ behaves as an active load.
By using properties of common gate (CG) amplifier,
Input impedance $\left(R_{i}\right)$ is low
Output impedance $\left(R_{0}\right)$ is high
So, it is a current amplifier.
Current amplifier is a current controlled current source.
 Question 2
A good transimpedance amplifier has
 A low input impedance and high output impedance. B high input impedance and high output impedance. C high input impedance and low output impedance. D low input impedance and low output impedance.
GATE EC 2018   Analog Circuits
Question 2 Explanation:
A good transimpedance amplifier should have low input impedance and low output impedance

 Question 3
A good transconductance amplifier should have
 A high input resistance and low output resistance B low input resistance and high output resistance C high input and output resistances D low input and output resistance
GATE EC 2017-SET-1   Analog Circuits
Question 3 Explanation:
A good transconductance amplifier should have very high input resistance and very high output resistance.
 Question 4
The desirable characteristics of a transconductance amplifier are
 A high input resistance and high output resistance B high input resistance and low output resistance C low input resistance and high output resistance D low input resistance and low output resistance
GATE EC 2014-SET-3   Analog Circuits
 Question 5
The feedback topology in the amplifier circuit ( the base bias circuit is not shown for simplicity) in the figure is
 A Voltage shunt feedback B Current series feedback C Current shunt feedback D Voltage series feedback
GATE EC 2014-SET-2   Analog Circuits
Question 5 Explanation:
The feedback topology in the amplifier circuit is
current series because
Sampling $\rightarrow$ Current
Mixing $\rightarrow$ Series
So current-series feedback

There are 5 questions to complete.