*3120*
3120
(Pages : 2)
Reg. No. : ..................................... Name : ..........................................
Third Semester B.Tech. Degree Examination, June 2009 (2003 Scheme) Branch : Computer Science 03.304 : ELECTRONICS CIRCUITS (RF) Time : 3 Hours
Max. Marks : 100 PART – A
Answer all questions. Each question carries 4 Marks. 1. What are the three configurations of clipping circuit ? 2. Define the terms : i) Leading edge ii) Trailing edge 3. Write the relation between rise time and upper 3dB frequency. 4. Why is monostable multivibrator also called a gating circuit ? 5. Discuss various ways of reducing drift in a dc amplifier. 6. Explain with circuit diagram the operation of an emitter follower. 7. What is twin-tub process ? 8. Compare the current spikes in ECL and TTL gates. 9. List the advantages of ion implantation technique. 10. What are the differences between 54 series and 74 series of TTL ICS ? (10Ă—4=40 Marks) P.T.O.
3120
*3031*
-2-
PART – B Answer one question from each Module. Each question carries 20 marks. Module – I 11. a) What is the basic differences between step up and step down switching regulator ? b) Draw the block diagram of a switch mode dc power supply and explain its working. 12. a) List the important types of power line disturbances. b) Draw the block diagram of a UPS and explain its working. Module – II 13. a) Draw the block diagram of an operational amplifier. Explain the functions of each block. b) For an npn BJT, it is found that at VBE = 0.7v, IB = 14.46 μ A and IE = 1.46 mA. Calculate α, β and Io. 14. Draw the circuit of a Colpitts oscillator and derive the expression for frequency of oscillation and condition for oscillation. Module – III 15. a) Draw the circuit of a TSL and explain its working. Mention its applications. b) Compare low power schottky TTL with standard TTL. 16. a) Explain the Czochralski method of crystal growth. b) Describe the term photolithography. –––––––––––––
(3×20=60 Marks)