EC 2251                                 ELECTRONIC CIRCUITS II                                  3  1  0  4

AIM
The aim of this course is to familiarize the student with the analysis and design of feed back amplifiers, oscillators, tuned amplifiers, wave shaping circuits, multivibrators and blocking oscillators.

OBJECTIVES
On completion of this course the student will understand
·         The advantages and method of analysis of feedback amplifiers
·         Analysis and design of LC and RC oscillators, tuned amplifiers, wave shaping circuits, multivibrators, blocking oscillators and time base generators.

UNIT 1            FEEDBACK AMPLIFIERS                                                                        9

Block diagram, Loop gain, Gain with feedback, Effects of negative feedback – Sensitivity and desensitivity of gain, Cut-off frequencies, distortion, noise, input impedance and output impedance with feedback, Four types of negative feedback connections – voltage series feedback, voltage shunt feedback, current series feedback and current shunt feedback, Method of identifying feedback topology and feedback factor, Nyquist criterion for stability of feedback amplifiers.

UNIT II            OSCILLATORS                                                                                         9

Classification, Barkhausen Criterion - Mechanism for start of oscillation and stabilization of amplitude, General form of an Oscillator, Analysis of LC oscillators - Hartley, Colpitts, Clapp, Franklin, Armstrong, Tuned collector oscillators, RC oscillators - phase shift – Wienbridge - Twin-T Oscillators, Frequency range of RC and LC Oscillators, Quartz Crystal Construction, Electrical equivalent circuit of Crystal, Miller and Pierce Crystal oscillators, frequency stability of oscillators.

UNIT III           TUNED AMPLIFIERS                                                                                            9

Coil losses, unloaded and loaded Q of tank circuits, small signal tuned amplifiers -  Analysis of capacitor coupled single tuned amplifier – double tuned amplifier -  effect of cascading single tuned and double tuned amplifiers on bandwidth – Stagger tuned amplifiers – large signal tuned amplifiers – Class C tuned amplifier – Efficiency and applications of Class C tuned amplifier - Stability of tuned amplifiers – Neutralization - Hazeltine neutralization method.

UNIT IV           WAVE SHAPING AND MULTIVIBRATOR CIRCUITS                            9

RC & RL Integrator and Differentiator circuits – Storage, Delay and Calculation of Transistor Switching Times – Speed-up Capaitor - Diode clippers, Diode comparator - Clampers. Collector coupled and Emitter coupled Astable multivibrator - Monostable multivibrator - Bistable multivibrators - Triggering methods for Bistable multivibrators -  Schmitt trigger circuit.

UNIT V            BLOCKING OSCILLATORS AND TIMEBASE GENERATORS              9

UJT sawtooth waveform generator, Pulse transformers – equivalent circuit – response - applications, Blocking Oscillator – Free running blocking oscillator - Astable Blocking Oscillators with base timing – Push-pull Astable blocking oscillator with emitter timing, Frequency control using core saturation, Triggered blocking oscillator – Monostable blocking oscillator with base timing – Monostable blocking oscillator with emitter timing, Time base circuits - Voltage-Time base circuit, Current-Time base circuit - Linearization through adjustment of driving waveform.

       TUTORIAL= 15                                                                                       TOTAL = 60

TEXT BOOKS
1.            Sedra / Smith, Micro Electronic Circuits Oxford University Press, 2004.
2.            S. Salivahanan, N. Suresh Kumar and A. Vallavaraj, Electronic Devices and Circuits, 2nd Edition, TMH, 2007.

REFERENCES
1.                  Millman J. and Taub H., Pulse Digital and Switching Waveforms, TMH, 2000.
2.                  Schilling and Belove, Electronic Circuits, 3rd Edition, TMH, 2002.
3.                  Robert L. Boylestad and Louis Nasheresky, Electronic Devices and Circuit Theory, 9th Edition, Pearson Education / PHI, 2002.
4.                  David A. Bell, Solid State Pulse Circuits, Prentice Hall of India, 1992.
5.                  Millman and Halkias. C., Integrated Electronics, TMH, 1991.