EC 2251 ELECTRONIC CIRCUITS II L T P C
3 1 0 4
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
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 I 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 PERIODS
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.
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.