EDC QB

FOR SECOND YEAR THIRD SEMESTER EEE Students

131303 - Electronic Devices and Circuits

UNIT I

1.      Explain the working of a PN junction forward bias and in reverse bias

2.      Explain the operation of zener diode and define zener breakdown. Draw its VI characteristics.

3.      With a neat sketch, explain the operation of PN junction diode

4.      Define regulator. Explain the operation of any one type of regulator.

5.      With a neat sketch, explain the operation of CLC and LC filter

UNIT II

1.   Draw and explain input and output characteristics of common emitter configuration of a transistor

2.   Explain in detail on voltage gain and current gain expressions for CB configuration using transistor hybrid model

3.   Draw the input and output characteristics of N-P-N transistor in common base configuration and explain it. How the different hybrid parameters are found out from the above characteristics

4.   Explain how the hybrid parameters hfe , hoe, hie, hre can be determined from the CE characteristics of a transistor .

UNIT III

1.   Explain the principle of operation of N-channel JFET

2.   Give a detailed description of construction and operation of JFET

3.   Explain the working principle and characteristics of Depletion N-MOSFET under depletion mode and enhancement mode in detail

4.   Derive the expression for A_v, R_i, and R_o for CS JFET amplifier

UNIT IV

1.   Draw the circuit diagram of a phase shift oscillator using BJT. Derive the expression for its frequency of oscillation. Determine the minimum h_fe for the transistor

2.   With suitable diagram explain the operation of Colpitts oscillator

3.   Explain the principle of operation of crystal oscillator and give its application

4.   Briefly discuss the effect of negative feedback on band width and stability of an amplifier

UNIT V

1.   Explain the operation of Schmitt trigger using two transistor for a sinusoidal input

2.   Explain the operation of UJT and draw the VI characteristics.

3.   explain series and shunt clipper with suitable diagram

4.   Draw the circuit diagram of collector coupled astable multivibrator and explain its operation with relevant operation. Derive the expression for time period