24031-ELECTRONIC DEVICES AND CIRCUITS IMPORTANT QUESTIONS

DIPLOMA IN ELECTRICAL AND ELECTRONICS ENGINEERING

SUBJECT CODE   : 24031 

SEMESTER           : III SEMESTER

 SUBJECT TITLE   : ELECTRONIC DEVICES AND CIRCUITS  

STAFF-IN-CHARGE: N.DILLIBABU

IMPORTANT QUESTIONS

UNIT-I

PART-A

1.     Give an example for donor impurity.

2.     What is the cut in voltage for silicon diode?

3.     What is the peak inverse voltage of full wave rectifier?

4.     Name a component used for filtering.

5.     Give an example for intrinsic semiconductor.

6.     Draw the symbol of Zener diode

7.     What is the efficiency of half-wave rectifier?

8.     How many filtering components are used in pi filter?

PART-B

1.     Explain the operation of Zener diode and draw characteristics.(oct-12,13,14)

2.     Explain the operation of full wave rectifier and draw its output waveforms. List out its applications.(apr-13,14)

3.     Explain the operation and characteristics of PN junction diode with suitable diagram.(apr-13,14)

4.     Explain the operation of C and pi filter and draw its waveform.

5.     With a neat diagram , explain the working of  bridge rectifier.(oct-12,13,14)

UNIT-II

PART-A

1.     Draw the symbol of NPN transistor.

2.     What is the formula for current gain in common emitter configuration?

3.     Which bias is normally used in applications?

4.     What is the need for negative feedback?

5.     In which region transistor has to be operated for faithful amplification?

6.     What is the output impedance of common base configuration?

7.     What is Q-point?

8.     Name the types of feedback

PART-B

1.     (i) Explain the operation of transistor as an amplifier.(oct-12)

(ii) Write short notes on fixed bias. (apr-13)

2.     (i) Explain the operation of emitter follower.

(ii) Explain how transistor is used as a switch(apr-13)

3.     (i)Explain the operation of NPN transistor.

(ii) Compare three different configurations of transistors. (apr-13)

4.     Explain the operation of RC coupled(oct-12) amplifier and draw its frequency response.

5.     Explain the effect of  negative feedback(oct-12)

6.     Explain the operation of  BJT(oct-13)

UNIT-III

PART-A

1.     What is the condition for oscillation?

2.     What is the output frequency of Heartley oscillator?

3.     Mention the relationship between the parameters of JFET.

4.     State any two applications of UJT

5.     What are the components used in tank circuit?

6.     State the advantages of crystal oscillator.

7.     Give an example for voltage controlled device.

8.     What is the formula for intrinsic standoff ratio?

PART-B

1       (i) Discuss about the conditions for oscillation.

(ii) Explain the operation of RC phase shift oscillator.

2       Explain the working principle of JFET and draw its characteristics.(oct-13)

3       (i) Explain the operation of Hartley oscillator.

(ii) Differentiate FET with BJT (oct-12)

4       Explain the construction and operation of UJT.(apr-13)

5       Explain the operation of crystal oscillator(oct-12)

6       Explain the operation of colpitts oscillator(apr-14)

UNIT-IV

PART-A

1.     Give an example for unidirectional switch.

2.     Draw the symbol of TRIAC.

3.     Name the terminals of DIAC.

4.     Expand MOSFET.

5.     What is the family name of SCR?

6.     How many terminals are present in TRIAC?

7.     Expand DIAC.

8.     What are the types of MOSFET?

PART-B

1       (i) Explain SCR as a controlled rectifier.                                                        ii) Discuss about the specifications of SCR.

2       Explain the operation of  DE-MOSFET with neat diagram.

3       With neat diagram explain the working principle of SCR and draw the transistor analogy of SCR.(oct-12)

4       i)  Explain the operation of DIAC with its characteristics. (apr-13)                               ii) Explain the construction details of MOSFET.

5       Explain the operation of TRIAC with its characteristics.(OCT-13)

UNIT-V

PART-A

1.     Draw the symbol of LDR.

2.     What is solar cell?

3.     Draw the output waveform of negative clamper.

4.     How many stable states are present in Astable  Multivibrator?

5.     In which bias, LED emits light?

6.     Expand LASER.

7.     What is the other name for Astable  Multivibrator?

8.     Draw the output waveform of negative clipper.

PART-B

1.     Explain the operation of Solar cell and Photo Transistor. (APR-13)

2.     Explain the operation of Schmitt Trigger and draw its output waveform.(APR-14)

3.     Explain the operation of  i) Opto interrupter ii) avalanche photo diode. (OCT-14)

4.     Explain the operation of positive and negative clamper.

5.     Explain the operation of CLIPPER(oct-12)

6.     Explain the operation of monostable multivibter(oct-12)

7.     Explain the operation of voltage diubler(oct-12)

8.     LED,LCD.