Categories

## EC8453 Question Bank Linear Integrated Circuits

### Sample EC8453 Question Bank Linear Integrated Circuits

(i) Derive the functional parameters for an inverting mode negative feedback gain circuit with a 741op-amp in IC inverting mode, with R1=1Kohm, Rf=40Kohm and compute Af, Rif, Rof, BW, offset voltage.

(ii) Discuss briefly on the differential mode Instrumentation amplifier. EC8453 Question Bank Linear Integrated Circuits

Examine the working principle of BJT differential amplifier with active load.

(i) Compose the concept of Widlar current source used in op-amp circuit with suitable circuit diagram and necessary equations.

Write note about LF155 JFET input operational amplifier and TL082 wide bandwidth dual JFET input operational amplifier with necessary diagram. EC8453 Question Bank Linear Integrated Circuits

State and explain about CMRR, Ad, Ac and suggest a method to improve CMRR.

Derive the transfer characteristics of dual input differential amplifier showing the linear and limiting regions. Comment on the same.

(i) A square wave peak-to-peak amplitude of 50mV has to be amplified to a peak-to-peak amplitude of 3V, with rise time of 4 μs or less. Can IC741 be used?
(ii) A IC741 Op-Amp whose slew rate is 0.5V/μs is used as an inverting amplifier with a gain of 50.The voltage gain Vs frequency curve of IC741 is flat up to 20 kHz. What maximum peak to peak input signal can be applied without distorting the output? EC8453 Question Bank Linear Integrated Circuits

Explain in detail the A.C analysis of dual input, balanced output differential amplifier or derive the expression for differential gain, common mode gain, CMRR, RI and RO of an emitter coupled differential amplifier.

Illustrate each direct current characteristics of operational amplifier with necessary equations and diagrams.

 Subject name Linear Integrated Circuits Semester 4 Subject Code EC8453 Regulation 2017 regulation

EC8453 Syllabus Linear Integrated Circuits

EC8453 Notes Linear Integrated Circuits

EC8453 Important Questions Linear Integrated Circuits

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## EC8453 Important Questions Linear Integrated Circuits

### Sample EC8453 Important Questions Linear Integrated Circuits

Define and explain slew rate. Derive its equation. Also explain method adapted to improving slew rate.

(i) Write down the characteristics and their respective values of an ideal operational amplifier.
(ii) Draw the circuit of basic current mirror and explain its operation. EC8453 Important Questions Linear Integrated Circuits

(i) Describe about output offset voltage. Explain methods to nullify offset voltage.
(ii) With neat circuit diagram, explain the operation of voltage reference circuit using temperature compensation.

(i) Discuss on current mirror with magnification.
(ii) Use appropriate block diagram, explain the general stages of an Op-Amp IC.

(i) What is input and output voltage and current offset? How are they compensated?
(ii) With a neat diagram derive the AC performance close loop characteristics of Op-amp to discuss on the circuit Bandwidth, Frequency response and slew rate. EC8453 Important Questions Linear Integrated Circuits

(i) Draw the circuit of basic current mirror and explain its operation.
(ii) Give the detail the DC analysis of a basic differential amplifier.

Obtain the expression for differential gain, common mode gain, CMRR, RI and RO of an emitter coupled differential amplifier.

(i) Sketch the Wilson current source and give short note about it. (ii) Using suitable diagram and necessary equations, explain the concept of Widlar current source used in op-amp circuit. EC8453 Important Questions Linear Integrated Circuits

Show the transfer characteristics of dual input differential amplifier showing the linear and limiting regions. Comment on the same.

 Subject name Linear Integrated Circuits Semester 4 Subject Code EC8453 Regulation 2017 regulation

EC8453 Syllabus Linear Integrated Circuits

EC8453 Notes Linear Integrated Circuits

EC8453 Question Bank Linear Integrated Circuits

Categories

## EC8453 Notes Linear Integrated Circuits

### OBJECTIVES: EC8453 Notes Linear Integrated Circuits

 To introduce the basic building blocks of linear integrated circuits
 To learn the linear and non-linear applications of operational amplifiers
 To introduce the theory and applications of analog multipliers and PLL
 To learn the theory of ADC and DAC
 To introduce the concepts of waveform generation and introduce some special function ICs

### OUTCOMES: EC8453 Notes Linear Integrated Circuits

Upon completion of the course, the student should be able to:
 Design linear and non linear applications of OP – AMPS
 Design applications using analog multiplier and PLL
 Design ADC and DAC using OP – AMPS
 Generate waveforms using OP – AMP Circuits
 Analyze special function ICs

### TEXT BOOKS: EC8453 Notes Linear Integrated Circuits

1. D.Roy Choudhry, Shail Jain, ―Linear Integrated Circuits‖, New Age International Pvt. Ltd., 2018, Fifth Edition. (Unit I – V)
2. Sergio Franco, ―Design with Operational Amplifiers and Analog Integrated Circuits‖, 4th Edition, Tata Mc Graw-Hill, 2016 (Unit I – V)

### REFERENCES: EC8453 Notes Linear Integrated Circuits

1. Ramakant A. Gayakwad, ―OP-AMP and Linear ICs‖, 4th Edition, Prentice Hall / Pearson Education, 2015.
2. Robert F.Coughlin, Frederick F.Driscoll, ―Operational Amplifiers and Linear Integrated Circuits‖, Sixth Edition, PHI, 2001.
3. B.S.Sonde, ―System design using Integrated Circuits‖ , 2nd Edition, New Age Pub, 2001.
4. Gray and Meyer, ―Analysis and Design of Analog Integrated Circuits‖, Wiley International,5th Edition, 2009.
5. William D.Stanley, ―Operational Amplifiers with Linear Integrated Circuits‖, Pearson Education,4th Edition,2001.
6. S.Salivahanan & V.S. Kanchana Bhaskaran, ―Linear Integrated Circuits‖, TMH,2nd Edition, 4th Reprint, 2016.

 Subject name Linear Integrated Circuits Semester 4 Subject Code EC8453 Regulation 2017 regulation

EC8453 Syllabus Linear Integrated Circuits

EC8453 Important Questions Linear Integrated Circuits

EC8453 Question Bank Linear Integrated Circuits

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## EC8453 Syllabus Linear Integrated Circuits

### UNIT I BASICS OF OPERATIONAL AMPLIFIERS 9 EC8453 Syllabus Linear Integrated Circuits

Current mirror and current sources, Current sources as active loads, Voltage sources, Voltage References, BJT Differential amplifier with active loads, Basic information about op-amps – Ideal Operational Amplifier – General operational amplifier stages -and internal circuit diagrams of IC 741, DC and AC performance characteristics, slew rate, Open and closed loop configurations – JFET Operational Amplifiers – LF155 and TL082.

### UNIT II APPLICATIONS OF OPERATIONAL AMPLIFIERS 9 EC8453 Syllabus Linear Integrated Circuits

Sign Changer, Scale Changer, Phase Shift Circuits, Voltage Follower, V-to-I and I-to-V converters, adder, subtractor, Instrumentation amplifier, Integrator, Differentiator, Logarithmic amplifier, Antilogarithmic amplifier, Comparators, Schmitt trigger, Precision rectifier, peak detector, clipper and clamper, Low-pass, high-pass and band-pass Butterworth filters.

### UNIT III ANALOG MULTIPLIER AND PLL 9 EC8453 Syllabus Linear Integrated Circuits

Analog Multiplier using Emitter Coupled Transistor Pair – Gilbert Multiplier cell – Variable transconductance technique, analog multiplier ICs and their applications, Operation of the basic PLL, Closed loop analysis, Voltage controlled oscillator, Monolithic PLL IC 565, application of PLL for AM detection, FM detection, FSK modulation and demodulation and Frequency synthesizing and clock synchronisation.

### UNIT IV ANALOG TO DIGITAL AND DIGITAL TO ANALOG CONVERTERS 9 EC8453 Syllabus Linear Integrated Circuits

Analog and Digital Data Conversions, D/A converter – specifications – weighted resistor type, R-2R
Ladder type, Voltage Mode and Current-Mode R – 2R Ladder types – switches for D/A converters, high speed sample-and-hold circuits, A/D Converters – specifications – Flash type – Successive
Approximation type – Single Slope type – Dual Slope type – A/D Converter using Voltage-to-Time Conversion – Over-sampling A/D Converters, Sigma – Delta converters.

### UNIT V WAVEFORM GENERATORS AND SPECIAL FUNCTION ICS 9 EC8453 Syllabus Linear Integrated Circuits

Sine-wave generators, Multivibrators and Triangular wave generator, Saw-tooth wave generator, ICL8038 function generator, Timer IC 555, IC Voltage regulators – Three terminal fixed and
adjustable voltage regulators – IC 723 general purpose regulator – Monolithic switching regulator, Low Drop – Out(LDO) Regulators – Switched capacitor filter IC MF10, Frequency to Voltage and Voltage to Frequency converters, Audio Power amplifier, Video Amplifier, Isolation Amplifier, Optocouplers and fibre optic IC.

 Subject name Linear Integrated Circuits Semester 4 Subject Code EC8453 Regulation 2017 regulation

EC8453 Notes Linear Integrated Circuits

EC8453 Important Questions Linear Integrated Circuits

EC8453 Question Bank Linear Integrated Circuits

Categories

## EC8451 Question Bank Electromagnetic Fields

### Sample EC8451 Question Bank Electromagnetic Fields

Obtain the expressions for differential area and volume element in
cylindrical coordinate system. (13)

7. Analyze the geometrical position of the point in Cartesian coordinate
system and obtain the algebraic equations. (13)

8. Express the space rate of change of a scalar in a given direction in terms of

9. Apply divergence theorem to find the divergence of the vector field in
curvilinear coordinate system. (13) EC8451 Question Bank Electromagnetic Fields

10. State and prove divergence theorem for a given differential volume
element. (13)

11. Assess the position of the vector field in spherical coordinate system and
derive the expressions for differential areas. (13)

12. Explain the difference between irrotational and solenoidal field using
Helmholtz theorem. (13)

13. (i)Verify the null identities using general orthogonal curvilinear
coordinates. (7) EC8451 Question Bank Electromagnetic Fields
(ii) How do you transform the vectors between Cartesian and cylindrical
systems? (6)

14. Elaborate the Stokes theorem with their applications.

(i) List out the properties of dielectric materials. (3)
(ii) Brief note on conductors and dielectrics in a static electric field. (10)

2. Derive the boundary conditions of the normal and tangential components of
electric field at the interface of two media with different dielectrics. EC8451 Question Bank Electromagnetic Fields

3. Obtain a formula for the electric field intensity on the axis of a circular disc
of radius b and carries uniform charge density ρs.

Formulate the energy required to assemble a uniform sphere of charge
with radius b and volume charge density ρ C/m3. (15)

4. Determine the E field both inside and outside a spherical cloud of electrons
with a uniform volume charge density ρ = – ρ0 for 0 ≤ R ≤ b and ρ =0 for
R>b by solving laplace and poisons equations for V.

 Subject name Electromagnetic Fields Semester 4 Subject Code EC8451 Regulation 2017 regulation

EC8451 Syllabus Electromagnetic Fields

EC8451 Notes Electromagnetic Fields

EC8451 Important Questions Electromagnetic Fields

Categories

## EC8451 Important questions Electromagnetic Fields

### Sample EC8451 Important questions Electromagnetic Fields

1. List the source quantities in the electromagnetic model.
2. Describe line, surface and volume charge density.
3. State divergence theorem.
4. Define Stokes theorem. EC8451 Important questions Electromagnetic Fields
5. Name the universal constants in the electromagnetic model.
6. What are surface and volume integrals?
7. Give the relationship between potential and electric field intensity.
8. Identify the unit vector and its magnitude corresponding to the given vector
A=5 âx + ây + 3 âz. EC8451 Important questions Electromagnetic Fields

9. Estimate the distance between the given vectors A (1, 2,3) and B (2,1,2).
10. Outline the relationship between magnetic flux density and field density.
11. Calculate the values of universal constants of free space. EC8451 Important questions Electromagnetic Fields
12. Analyze a differential volume element in spherical coordinates (r,θ,φ)
resulting from differential charges in the orthogonal coordinate systems.

13. Specify the unit vector extending from the origin towards the point G (2,-
2,-1).

14. Compare orthogonal and non-orthogonal coordinate systems.
15. Point out the role of vector algebra in electromagnetics. EC8451 Important questions Electromagnetic Fields

and circuit theory. (13)

2. Tabulate the various field, source and universal quantities of
electromagnetic model and explain.

(i)Write short notes on vector algebra. (5)
(ii) Given the two vectors A and B , How do you find
a) The component of A in the direction of B
b) The component of B in the direction of A (8)

4. Explain how an orthogonal co-ordinate system describes the position of the
point in free space. (13)

5. Summarize about the curl of a vector field in cylindrical and spherical
coordinates.

 Subject name Electromagnetic Fields Semester 4 Subject Code EC8451 Regulation 2017 regulation

EC8451 Syllabus Electromagnetic Fields

EC8451 Notes Electromagnetic Fields

EC8451 Question Bank Electromagnetic Fields

Categories

## EC8451 Notes Electromagnetic Fields

### OBJECTIVES: EC8451 Notes Electromagnetic Fields

 To gain conceptual and basic mathematical understanding of electric and magnetic fields in free space and in materials
 To understand the coupling between electric and magnetic fields through Faraday’s law, displacement current and Maxwell’s equations
 To understand wave propagation in lossless and in lossy media
 To be able to solve problems based on the above concepts

### OUTCOMES: EC8451 Notes Electromagnetic Fields

By the end of this course, the student should be able to:
 Display an understanding of fundamental electromagnetic laws and concepts
 Write Maxwell’s equations in integral, differential and phasor forms and explain their physical meaning  Explain electromagnetic wave propagation in lossy and in lossless media
 Solve simple problems requiring estimation of electric and magnetic field quantities based on these concepts and laws

### TEXT BOOKS: EC8451 Notes Electromagnetic Fields

1. D.K. Cheng, Field and wave electromagnetics, 2nd ed., Pearson (India), 1989 (UNIT I, II,III IV,V)
2. W.H. Hayt and J.A. Buck, Engineering electrmagnetics, 7th ed., McGraw-Hill (India), 2006 (UNIT I-V)

### REFERENCES EC8451 Notes

1. D.J. Griffiths, Introduction to electrodynamics, 4th ed., Pearson (India), 2013
2. B.M. Notaros, Electromagnetics, Pearson: New Jersey, 2011
3. M.N.O. Sadiku and S.V. Kulkarni, Principles of electromagnetics, 6th ed., Oxford (Asian Edition), 2015

 Subject name Electromagnetic Fields Semester 4 Subject Code EC8451 Regulation 2017 regulation

EC8451 Syllabus Electromagnetic Fields

EC8451 Important Questions Electromagnetic Fields

EC8451 Question Bank Electromagnetic Fields

Categories

## EC8451 Syllabus Electromagnetic Fields

### UNIT I INTRODUCTION 12 EC8451 Syllabus Electromagnetic Fields

Electromagnetic model, Units and constants, Review of vector algebra, Rectangular, cylindrical and spherical coordinate systems, Line, surface and volume integrals, Gradient of a scalar field, Divergence of a vector field, Divergence theorem, Curl of a vector field, Stoke’s theorem, Null identities, Helmholtz’s theorem

### UNIT II ELECTROSTATICS 12 EC8451 Syllabus Electromagnetic Fields

Electric field, Coulomb’s law, Gauss’s law and applications, Electric potential, Conductors in static electric field, Dielectrics in static electric field, Electric flux density and dielectric constant, Boundary conditions, Capacitance, Parallel, cylindrical and spherical capacitors, Electrostatic energy, Poisson’s and Laplace’s equations, Uniqueness of electrostatic solutions, Current density and Ohm’s law, Electromotive force and Kirchhoff’s voltage law, Equation of continuity and Kirchhoff’s current law

### UNIT III MAGNETOSTATICS 12 EC8451 Syllabus Electromagnetic Fields

Lorentz force equation, Law of no magnetic monopoles, Ampere’s law, Vector magnetic potential, Biot-Savart law and applications, Magnetic field intensity and idea of relative permeability, Magnetic circuits, Behaviour of magnetic materials, Boundary conditions, Inductance and inductors, Magnetic energy, Magnetic forces and torques

### UNIT IV TIME-VARYING FIELDS AND MAXWELL’s EQUATIONS 12

Faraday’s law, Displacement current and Maxwell-Ampere law, Maxwell’s equations, Potential functions, Electromagnetic boundary conditions, Wave equations and solutions, Time-harmonic fields

### UNIT V PLANE ELECTROMAGNETIC WAVES 12

Plane waves in lossless media, Plane waves in lossy media (low-loss dielectrics and good conductors), Group velocity, Electromagnetic power flow and Poynting vector, Normal incidence at
a plane conducting boundary, Normal incidence at a plane dielectric boundary

 Subject name Electromagnetic Fields Semester 4 Subject Code EC8451 Regulation 2017 regulation

EC8451 Notes Electromagnetic Fields

EC8451 Important Questions Electromagnetic Fields

EC8451 Question Bank Electromagnetic Fields

Categories

## EC8491 Question Bank Communication Theory

### Sample EC8491 Question Bank  Communication Theory

(i) Outline the function of switching modulator in the
generation of AM signal. (7)

(ii) The tuned circuit of the oscillator in a simple AM
transmitter employs a 40μH coil and 12nF capacitor. If the oscillator output is modulated by audio frequency of 5KHz, what are the lower and upper sideband frequencies and the bandwidth required. EC8491 Question Bank Communication Theory

(i) Demonstrate the concepts of envelope detection for demodulation of AM and explain its operation. (7)

Give main idea about super heterodyne receiver with neat block diagram and explain the various parameters. (13)

Identify the need for carrier suppression in AM system? EC8491 Question Bank Communication Theory

Draw and explain the functioning of such system. (13)

Construct the balanced modulator circuit for the generation of DSB-SC-AM and explain its operation.

How do you examine ring modulator for the generation of DSB-SC signal? (13)

Analyse the significance of SSB-SC and elaborate in detail about filter method of suppression of unwanted sidebands. (13)

i) Assesss the generation of SSBSC signal using phase shift method. (7)

ii) How would you generate SSB using Weavers method? Illustrate with a neat block diagram.

i) An audio frequency signal 10sin2П*500t is used to
amplitude modulate a carrier of 50sin2П*105t. Calculate modulation index, amplitude of each sideband frequencies, bandwidth and total power delivered to the load of 600Ω. (7)

ii) Discuss on pre-envelope and complex envelope. (6) EC8491 QB Communication Theory

 Subject name Communication Theory Semester 4 Subject Code EC8491 Regulation 2017 regulation

EC8491 Syllabus Communication Theory

EC8491 Notes Communication Theory

EC8491 Important Questions Communication Theory

Categories

## EC8491 Important Questions Communication Theory

### Sample EC8491 Important Questions  Communication Theory

1. What is pre envelope and complex envelope?
2. Give the advantages of VSB-AM.
3. State heterodyning principle.  EC8491 Important Questions  Communication Theory
Mention the advantages of modulating low frequency signal into high frequency signal.
5. List the types of AM modulators.
6. Define Coherent Detection.
7. Why do you need modulation in communication systems?
8. Identify the differences between single sideband and vestigial sideband systems. EC8491 Important Questions  Communication Theory
9. Write about diagonal clipping and negative peak clipping?
Suggest a modulation scheme for broadcast video
transmission.
Apply the concepts of sensitivity and selectivity in AM
Draw the AM modulated wave for over, under & 100%
modulation.
If incoming frequency is f1 and translated carrier frequency is f2, apply and find the local oscillator frequency.
14. Compare AM with DSB-SC and SSB-SC.
15. Distinguish between high level and low level modulation?
16. Differentiate between linear and non-linear modulation

17. A carrier of 20MHz is amplitude modulated with a signal frequency of 3KHz and amplitude 5Volts. If modulation index is 0.5, determine the spectra of the waveform. EC8491 Important Questions  Communication Theory

18. If a 10KW amplitude modulated transmitter is modulated sinusoidally by 50%, evaluate the total RF power delivered.

19. Summarize the methods for generating SSB-SC signal.
20. Can you formulate the theory for modulation index of an AM signal and write its classification

Describe the concepts of AM modulation and derive the equation of an AM wave. Draw the phasor diagram, spectrum and modulated AM wave for various degrees of modulation index.

 Subject name Communication Theory Semester 4 Subject Code EC8491 Regulation 2017 regulation