Download Model question papers & previous years question papers
|
Posted By: Sree.... Member Level: Diamond Posted Date: 10 Mar 2008
|
2007 Andhra Pradesh State Jawaharlal Nehru Technological University B.Tech BASIC ELECTRONICS(R05) Set No. 3 Question paper
|
|
|
Code No: R05220301 Set No. 3
II B.Tech II Semester Regular Examinations, Apr/May 2007
BASIC ELECTRONICS
( Common to Mechanical Engineering and Production Engineering)
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) Explain what is meant by mobility of a charge carrier in a solid. Derive
an expression for the conductivity of a semiconductor, containing both free
electrons and holes, in terms of the concentrations n and p and the mobilities.
(b) Draw the circuit of Bridge rectifier and explain the working of it. [8+8]
2. (a) Sketch a family of CB input characteristics of a transistor and explain the
shape of the characteristics qualitatively.
(b) Derive the relation between a and ß of a transistor.
(c) Define trans-conductance & drain resistance of J F E T. Give their units.
[6+6+4]
3. (a) Draw two - transistor model of SCR and explain the working of SCR.
(b) Draw the circuit symbols of SCR, DIAC and TRIAC. Give the conducting
properties of the above. [10+6]
4. (a) Distinguish between voltage feedback and current feedback in amplifiers.
(b) Draw the block diagram of a negative feedback amplifier to show increase
in input impedance and derive the expression for input impedance Zif of
feedback amplifier in terms of the input impedance Zi and gain A of the
amplifier without feedback and feed-back factor ß.
(c) If input impedance and gain of an amplifier without feedback are 1k
and
1000 respectively and feedback factor is 0.01, determine the value of input
impedance of the feedback amplifier. [4+8+4]
5. (a) Why phase shift through the R-C feed back network of R-C phase shift oscil-
lator is to be 1800? Explain.
(b) What are the limitations of R C-Phase shift oscillators?
(c) Draw the circuit of Colpitts Oscillator and explain the working of it. [5+3+8]
6. (a) Name principal types of resistance welding processes and briefly explain them.
(b) Briefly explain the principle of working of any one type of Thermal Timers.
[12+4]
7. (a) Draw a neat sketch and explain the working of CR tube.
(b) Discuss about the electrodes used in dielectric heating. Explain, when the air
clearance, is permitted between the Dielectric material and one or both the
electrodes used in Dielectric heating. [8+8]
1 of 2
Code No: R05220301 Set No. 3
8. (a) Derive an expression for an output voltage of R-2R ladder DAC.
(b) The digital input for a 4-bit DAC is 0110. Calculate its final output voltage.
[8+8]
? ? ? ? ?
2 of 2
Return to question paper search
|
|
|
Submit Previous Years University Question Papers and
make money from adsense revenue sharing program
Are you preparing for a university examination? Download model question papers
and practise before you write the exam.