Anna University Chennai 2005 B.E Electronic Instrumentation

B.E/B.TECH. DEGREE exam ,MAY/JUNE 2005
Second semester,EI
Electrical Machine


Time:3 Hrs
Maximum: 100 marks



PART A (10 X two = 20)


1.What is the thickness of depletion regeion of PN junction?

2.Define diffusion capacitance of a PN junction diode.

3. What is emitter efficiency of a transisitor?

4.Name the transistor switching times

5. What is the operating regeion of JFET for amplifier application?

6.State 2 principle applications of UJT.

7.What is photovoltaic effect?

8.What is function of solar cell?

9.Show the reverse bias cjarecteristics of zener diode.

10.Give the basic structure of SCR.


PART B ( five X 16= 80)


11. (i) Derive the current components in a transistor with forward biased emitter junction and reversed biased collector junction.

(ii)Draw the hybrid model of CE transistor and describe the parametrs.

12(a) (i)Explain the principle of operation of a PN junction diode with its VI charecteristics.

(ii)Explain the temperature depedndence of PN junction charecteristics

OR

(b) (i)Describe the transition capacitance of PN junction diode

(ii)Explain the diode switching times.

13(a) (i)List out the advantages of FET over conventional transistor

(ii)Discuss the basic structure,operation and charectristics of JFET.

OR

(b) (i)Discuss the output and transfer charecteristics of an E-MOSFET

(ii)Explain the construction and working of UJT.

14(a) (i)Expalin the construction and operation with VI charecteristics of a photo diode.

(ii)Explain the working principle of LED and comparre with LCD.Describe the 7 segment display system using LED

OR

(b) (i)Explain the construction and operation with VI charecteristics of a photo transistor.

(ii)Discuss about opto couplers

15 (a) (i)Discuss the construction and operation wth Vi charecteristics of a TRIAC .Specify any 2 applications of TRIAC.

(ii)Discuss about varactor diode

OR

(b) (i) discuss the structure,operation and charecteristics of a tunnel diode.

(ii)Write short notes on CCDs

Earning:   Approval pending.