Discrete Electronic Circuits - May 2014
Electronics Engineering (Semester 4)
TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.
Solve any four:-
1 (a) For the following clipper circuit sketch the i/p and o/p wave form write equation for Vo. (5 marks) 1 (b) Compare BJT, JFET and MOSFET(5 marks) 1 (c) Which components in an amplifier (CS and CE) circuit affect low frequency response? Explain.(5 marks) 1 (d) State and explain Barkhansen's criteria.(5 marks) 1 (e) Explain effect of swapping resistor in differential amplifier.(5 marks) 1 (f) Derive expression of efficiency of clan A Transformer coupled amplifier.(5 marks) 2 (a) Draw approximate hybrid π model of CE transistor amplifier and derive expressions for Av, Ai, Zi and Zo.(10 marks) 2 (b) Determine operating point and draw DC load line for the circuit shown:- (10 marks) 3 (a) Draw two stage CS-CS amplifier circuit and derive expressions for Av, Zi and Zo.(10 marks) 3 (b) State different types of negative feedback topologies and explain current series in detail using block diagram.(10 marks) 4 (a) Draw circuit diagram for dual i/p balanced o/p differential amplifier (using any type of devices) and derive expressions for Ad, Ac, CMRR and Ri.(10 marks) 4 (b) Draw circuit diagram of colpitt's oscillator and explain it's working. State applications, advantages and disadvantages of this circuit.(10 marks) 5 (a) Justify need for constant current source and explain any one in detail.(10 marks) 5 (b) Explain working of class B (push-pull) power amplifier.(10 marks) 6 (a) For the circuit shown find Av, Ri and Ro. (10 marks) 6 (b) Draw High frequency model for CS JFET amplifier and explain.(5 marks) 6 (c) Explain importance and need for biasing in amplifier.(5 marks)