JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD · I · St · B.Tech Supplementary Examinations June â 2009 · SEMICON
NR
Code No: NR10205
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD I St B.Tech Supplementary Examinations June – 2009 SEMICONDUCTORS AND DEVICES AND CIRCUITS (Common to EEE,ECE,CSE,CSIT,EIE,BME, E.CONT.E,ETM ,ECC and CSSE) Max Marks: 80 Answer any FIVE Questions. All Questions carries equal marks. -----
.in
Time: 3 hours
Define deflection sensitivity for electrostatic and magnetic deflections. What are the application of C.R.O. Explain them clearly.
2.a) b)
Explain about forward and reverse bias V-I characteristics of pn junction diode? Explain clearly about avalanche and zener breakdown phenomena.
3.a) b)
Compare and contrast CE,CB and CC configuration of BJT. What are h-parameters? Define them. Draw the h-parameters model of BJT.
4.a)
What are the characteristics of FET. Why the FET is called voltage controlled devices? Give the constructional features of UJT and draw it V-I characters tics.
5.a) b) 6.a) b) 7.a)
What are the advantages and disadvantages of negative feedback? What are the conditions for sustained oscillators? Draw the colpitts oscillators circuit and in that C2=10nF, L=110µF. Find feedback factors and operating frequency.
nt
b)
What is biasing? What are different types? Draw the circuit of self bias circuit and explain. Derive the expressions for AI and A of CE amplifier circuit. In a CE amplifier circuit, Re=5kΩ, RS=1.2Ω, ufe=100, hie=1.1kΩ, hoe=25µ . Find Ri, Ai, Ai, and RO. Define fα,fβ,fT and gain bandwidth product of HF model of a transistor.
uW
b)
or ld
1.
Compare class A,B and C power amplifiers. Explain the principles of push-pull power amplifier.
Aj
8.a) b)
x-x-x
