Questions & Answers of Operational Amplifiers – Characteristics and Applications

Question No. 112

The circuit shown below is an example of a


Question No. 137

For the circuit shown below, taking the opamp as ideal, the output voltage Vout in terms of the input voltages V1 , V2 and V3 is


Question No. 17

Of the four characteristic given below, which are the major requirements for an instrumentation amplifier?
P. High common mode rejection ratio
Q. High input impedance
R. High linearity
S. High output impedance

Question No. 23

Consider the circuit shown in the figure,. In this circuit R = 1kΩ, and C=1μF. The input voltage is sinusoidal with a frequency of 50 Hz, represented as phasor with magnitude Vi and phase angle 0 radian as shown in the figure. The output voltage is represented as a phasor with magnitude V0 and phase angle δ radian. What is the value of the output phase angle δ (in radian) relative to the phase angle of the input voltage?

Question No. 49

The op-amp shown in the figure has a finite gain A = 1000 and an infinite input resistance. A step-voltage Vi= 1 mV is applied at the input at time t = 0 as shown. Assuming that the operational amplifier is not saturated, the time constant (in millisecond) of the output voltage V0 is

Question No. 121

The operational amplifier shown in the figure is ideal. The input voltage (in Volt) is V1= 2sin2π×2000t. The amplitude of the output voltage V0 (in Volt) is ________.

Question No. 124

The filters F1 and F2 having characteristics as shown in Figures (a) and (b) are connected as shown in Figure (c).

The cut-off frequencies of F1 and F2 are f1 and f2 respectively. If f1< f2, the resultant circuit exhibits the characteristics of a

Question No. 149

The saturation voltage of the ideal op-amp shown below is ±10 V. The output voltage v0 of the following circuit in the steady-state is

Question No. 59

Given that the op-amps in the figure are ideal, the output voltage V0 is

Question No. 61

In the figure shown, assume the op-amp to be ideal. Which of the alternatives gives the correct Bode plots for the transfer function V0ωViω ?

Question No. 232

An operational-amplifier circuit is shown in the figure.

The output of the circuit for a given input vi is

Question No. 260

The transfer characteristic of the Op-amp circuit shown in figure is

Question No. 1

In the circuit shown below what is the output voltage (Vout) in Volts if a silicon transistor Q and an ideal op-amp are used?

Question No. 39

In the circuit shown below the op-amps are ideal. Then Vout in Volts is

Question No. 32

The circuit shown is a

Question No. 11

A low – pass filter with a cut-off frequency of 30Hz is cascaded with a high-pass filter with a cut-off frequency of 20Hz. The resultant system of filters will function as

Question No. 12

for the circuit shown below

The CORRECT transfer characteristic is

Question No. 21

Given that the op-amp is ideal, the output voltage V0 is

Question No. 12

The nature of feedback in the opamp circuit shown is

Question No. 21

The following circuit has R = 10kΩ, C = 10µF The input voltage is a sinusoid at 50Hz with an rms value of 10V. Under ideal conditions, the current iS from the source is

Question No. 23

Transformer and emitter follower can both be used for impedance matching at the output of an audio amplifier. The basic relationship between the input power Pin and output power Pout in both the cases is

Question No. 41

An ideal opamp circuit and its input waveform are shown in the figures. The output waveform of this circuit will be

Question No. 42

The block diagrams of two types of half wave rectifiers are shown in the figure. The transfer characteristics of the rectifiers are also shown within the block.

It is desired to make full wave rectifier using above two half-wave rectifiers. The resultant circuit will be





Question No. 46

A waveform generator circuit using OPAMPs is shown in the figure. It produces a triangular wave at point ‘P’ with a peak to peak voltage of 5 V for Vi = 0 V.

If the voltage Vi is made +2.5 V, the voltage waveform at point ‘P’ will become





Question No. 80

A general filter circuit is shown in the figure:

If R1 = R2 = RA and R3 = R4 = RB, the circuit acts as a

Question No. 81

A general filter circuit is shown in the figure:

The output of the filter in Q.80 is given to the circuit shown in figure :
The gain v/s frequency characteristic of the output (vo) will be





Question No. 7

The circuit shown in the figure is

Question No. 24

The switch S in the circuit of the figure is initially closed, it is opened at time t = 0. You may neglect the zener diode forward voltage drops. What is the behavior of VOUT for t > 0?