Feedback Amplifier
Practice QuestionsMarks 1
1
For the closed loop amplifier circuit shown below, the magnitude of open loop low frequency small signal voltage gain is 40. All the transistors are biased in saturation. The current source $I_{ss}$ is ideal. Neglect body effect, channel length modulation and intrinsic device capacitances. The closed loop low frequency small signal voltage gain $\frac{v_{out}}{v_{in}}$ (rounded off to three decimal places) is ____.
GATE ECE 2024
2
A cascade of common-source amplifiers in a unity gain feedback configuration oscillates when
GATE ECE 2023
3
In the ac equivalent circuit shown in the figure, if i$${_F}$$ is very large, the type of feedback is
GATE ECE 2014 Set 1
4
A good current buffer has
GATE ECE 2014 Set 1
5
The desirable characteristics of a transconductance amplifier are
GATE ECE 2014 Set 3
6
The feedback topology in the amplifier circuit (the base bias circuit is not shown for simplicity) in the figure is 
GATE ECE 2014 Set 2
7
In a voltage-voltage feedback as shown below, which one of the following statements is TRUE, if the gain k is increased? 
GATE ECE 2013
8
In a shunt-shunt negative feedback Amplifier, as compared to the basic Amplifier,
GATE ECE 1998
9
To obtain very high input and output impedances in a feedback Amplifier, the mostly used is
GATE ECE 1995
10
Negative feedback in Amplifiers.
GATE ECE 1993
Marks 2
1
Voltage series feedback (also called series-shunt feedback) results in
GATE ECE 2004
2
An amplifier without feedback has a voltage gain of 50, input Resistance of 1 k$$\Omega $$ and output Resistance of 2.5 k$$\Omega $$ . The input Resistance of the current-shunt negative feedback factor of 0.2 is
GATE ECE 2003
3
In a negative feedback amplifier using voltage - Series (i.e., voltage - sampling, series mixing) feedback
GATE ECE 2002
4
The most commonly used Amplifier in sample and hold circuit is
GATE ECE 2000
5
An amplifier has an open loop gain of 100, an input impedance of 1 k$$_\Omega $$, and an output impedance of 100 $$_\Omega $$ . A feedback network with a feedback factor of 0.99 is connected to the amplifier an a voltage series feedback mode. The new input and output impedance respectively are
GATE ECE 1999
6
Negative feedback in an amplifier
GATE ECE 1999
7
Negative feedback in
1. Voltage series configuration
2.Current shunt configuration
(a) increases input impedance
(b) decreases input impedance
(c) increases closed loop gain
(d) leads to ascillation.
GATE ECE 1997
8
Two non-inverting amplifiers, one having a unity gain and other having a gain of twenty, are made using identical operational gain amplifier, the amplifier with gain twenty has
GATE ECE 1991
9
The feedback amplifier shown in Fig.has:
GATE ECE 1989