Andhra University BE/B.Tech Electronics Previous Paper 2006
First question is compulsory
Answer any FOUR questions from the remaining questions.
All questions carry equal marks
Answer ALL parts of any question at one place
1.(a) List any two applications of CC amplifier.
(b) List any three types of biasing circuits
(c) Draw the forward and reverse characteristics of Schottky diode.
(d) List any two advantages of FET over BJT
(e) What is meant by tunneling?
(f) Draw the i/p and o/p waveforms of s fullwave rectifier
(g) Explain the principle and working of a Zener diode
2.(a) What is a PN junction? Explain the formation of depletion layer in a PN junction.
(b) Explain what a hole is . How do they move in the intrinsic semiconductor.
3. (a) Explain how the the process of avalanche breakdown occurs in a PN junction. How it is different from a Zener breakdown?
(b) Draw and explain the forward and reverse characteristic of a varactor diode.
4. (a) Sketch and explain the V-I characteristics of an NPN Transistor in common emitter operation and indicate theorem the different regions of importance.
(b) A certain transistor has L of 0.98 and a collector leakage current Ico of 1µA . calculate the collector current and the base currents , when IB=1mA.
5. (a) the datasheet of a certain JFET indicates that IDss=15mA and Vgs(OFF)=-5V. Determine the drain current for VGS=0V,-1V and -4V.
(b)Explain with the help of neat diagram , the structure of a N-Channel FET ,and its Volt –ampere characteristics. In what ways it is different from a bipolar Junction Transistor.
6.(a) Draw the circuit diagram of a full wave rectifier with center-tap connection. Explain their working.
(b) A π filter in a Full-wave rectifier uses C1=C2=100µf and L=10H. The load current is 0.5A at 100V d.c .Find the ripple factor
7. (a) Draw a voltage divider bias circuit and derive an expression for its stability factor.
(b) What is the collector current in a circuit shown below. Also determines Vb,VE,VC voltages with respect to ground .
8.(a) Draw the circuit diagram of a common emitter with emitter and voltage divider biasing circuit.
(b) Discuss the merits and limitations of common base amplifier.http://www.stepinau.com/2013/09/26/andhra-university-beb-tech-electronics-previous-paper-2006/IT 2.1 Previous PapersCSE,CSE Previous Papers,Electronics Previous Papers,IT,IT Previous Papers