Question 1 |
A good transimpedance amplifier has
low input impedance and high output impedance. | |
high input impedance and high output impedance. | |
high input impedance and low output impedance. | |
low input impedance and low output impedance. |
Question 1 Explanation:
A good transimpedance amplifier should have low
input impedance and low output impedance
Question 2 |
A good transconductance amplifier should have
high input resistance and low output resistance | |
low input resistance and high output resistance | |
high input and output resistances | |
low input and output resistance |
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
high input resistance and high output resistance | |
high input resistance and low output resistance | |
low input resistance and high output resistance | |
low input resistance and low output resistance |
Question 4 |
The feedback topology in the amplifier circuit ( the base bias circuit is not shown
for simplicity) in the figure is
Voltage shunt feedback | |
Current series feedback | |
Current shunt feedback | |
Voltage series feedback |
Question 4 Explanation:
The feedback topology in the amplifier circuit is
current series because
Sampling \rightarrow Current
Mixing \rightarrow Series
So current-series feedback
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
voltage-voltage feedback | |
voltage-current feedback | |
current-voltage feedback | |
current-current feedback |
Question 5 Explanation:
Sampling \rightarrow current
Mixing \rightarrow voltage
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?
The input impedance increases and output impedance decreases. | |
The input impedance increases and output impedance also increases. | |
The input impedance decreases and output impedance also decreases. | |
The input impedance decreases and output impedance increases. |
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}
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 lage input resistance and a large output resistance | |
a large input resistance and a small output resistance | |
a small input resistance and a large output resistance | |
a small input resistance and a small output resistance |
Question 8 |
The input impedance (Z_{i}) and the output impedance (Z_{0}) of an ideal transconductance (voltage controlled current source) amplifier are
Z_{i}=0,Z_{0}=0 | |
Z_{i}=0,Z_{0}=\infty | |
Z_{i}=\infty ,Z_{0}=0 | |
Z_{i}=\infty ,Z_{0}=\infty |
Question 9 |
The effect of current shunt feedback in an amplifier is to
increase the input resistance and decrease the output resistance | |
increases both input and output resistance | |
decrease both input and output resistance | |
decrease the input resistance and increase the output resistance |
Question 10 |
Voltage series feedback (also called series-shunt feedback) results in
increase in both input and output impedances | |
decrease in both input and output impedances | |
increase in input impedance and decrease in output impedance | |
decrease in input impedance and increase in output impedance |
There are 10 questions to complete.