B.E. III Sem Electronics & Communication Engineering

III SEMESTER

3EC2. Electronic Devices & Circuits

 

UNIT 1 : SEMICONDUCTOR PHYSICS : Mobility and conductivity, charge densities in a semiconductor, Fermi Dirac distribution, carrier concentrations and fermi levels in semiconductor, Generation and recombination of charges, diffusion and continuity equation, Mass action Law, Hall effect.


UNIT 2 : Junction diodes,Diode as a ckt. element, load line concept, clipping and clamping circuits, Voltage multipliers. Construction, characteristics and working principles of UJT


UNIT 3 : Transistor characteristics, Current components, Current gains: alpha and beta. Operating point. Hybrid model, h-parameter equivalent circuits. CE, CB and CC configuration. DC and AC analysis of CE,CC and CB amplifiers. Ebers-Moll model. Biasing & stabilization techniques. Thermal runaway, Thermal stability.


UNIT 4 : JFET, MOSFET, Equivalent circuits and biasing of JFET's & MOSFET’s. Low frequency CS and CD JFET amplifiers. FET as a voltage variable resistor.


UNIT 5 : SMALL SIGNAL AMPLIFIERS AT LOW FREQUENCY :
Analysis of BJT and FET, DC and RC coupled amplifiers. Frequency response, midband gain, gains at low and high frequency. Analysis of DC and differential amplifiers, Miller's Theorem. Cascading Transistor amplifiers, Darlington pair. Emitter follower, source follower.