Feedback Amplifiers

Question 1
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 1 Explanation: 
A good transimpedance amplifier should have low input impedance and low output impedance
Question 2
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 2 Explanation: 
A good transconductance amplifier should have very high input resistance and very high output resistance.
Question 3
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 4
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 4 Explanation: 
The feedback topology in the amplifier circuit is
current series because
Sampling \rightarrow Current
Mixing \rightarrow Series
So current-series feedback
Question 5
In the ac equivalent circuit shown in the figure, if i_{in} is the input current and R_{F} is very larger, the type of feedback is
A
voltage-voltage feedback
B
voltage-current feedback
C
current-voltage feedback
D
current-current feedback
GATE EC 2014-SET-1   Analog Circuits
Question 5 Explanation: 
Sampling \rightarrow current
Mixing \rightarrow voltage
Question 6
In a voltage-voltage feedback as shown below, which one of the following statements is TRUE if the gain k is increased?
A
The input impedance increases and output impedance decreases.
B
The input impedance increases and output impedance also increases.
C
The input impedance decreases and output impedance also decreases.
D
The input impedance decreases and output impedance increases.
GATE EC 2013   Analog Circuits
Question 6 Explanation: 
The given configuration is a voltage-series feedback configuration.
So, the input impedance increases
R_{i f}=R_{i}\left(1+A_{0} K\right)
and, the output impedance decreases
R_{o f}=\frac{R_{o}}{1+A_{o} K}
Question 7
In a transconductance amplifier, it is desirable to have
A
a lage input resistance and a large output resistance
B
a large input resistance and a small output resistance
C
a small input resistance and a large output resistance
D
a small input resistance and a small output resistance
GATE EC 2007   Analog Circuits
Question 8
The input impedance (Z_{i}) and the output impedance (Z_{0}) of an ideal transconductance (voltage controlled current source) amplifier are
A
Z_{i}=0,Z_{0}=0
B
Z_{i}=0,Z_{0}=\infty
C
Z_{i}=\infty ,Z_{0}=0
D
Z_{i}=\infty ,Z_{0}=\infty
GATE EC 2006   Analog Circuits
Question 9
The effect of current shunt feedback in an amplifier is to
A
increase the input resistance and decrease the output resistance
B
increases both input and output resistance
C
decrease both input and output resistance
D
decrease the input resistance and increase the output resistance
GATE EC 2005   Analog Circuits
Question 10
Voltage series feedback (also called series-shunt feedback) results in
A
increase in both input and output impedances
B
decrease in both input and output impedances
C
increase in input impedance and decrease in output impedance
D
decrease in input impedance and increase in output impedance
GATE EC 2004   Analog Circuits
There are 10 questions to complete.