Electronic Circuits and Devices Question Paper of 3rd Semester ECE16 Download Previous Years Question Paper 1

Electronic Circuits and Devices

(EC-201, Dec-07)

Section-A

1).

 a). Discuss the behavior of p-n junction diode under forward and reverse biased

conditions.

b). Draw circuit diagram for CC and CE configuration of transistor. Which is having  higher gain and why.

c). State advantages of JFET over BJT.

d). What is operating point? Why is it necessary to stabilize operating point of a

transistor amplifier?

e). What do you understand by class A,B and C power amplifiers.

f). Draw the block diagram of a multistage amplifier having n-stages. Write

expression for its gain (A).

g). State advantages of –ve feedback in amplifiers.

h). What is an oscillator? What are the essential components of feed back LC

oscillator?

i). Differentiate between photo diodes and photo transistor.

j). Define term junction capacitance. Name different type of capacitances diode

posses.

Section-B

2). Define stability factor. Explain with circuit diagram of potential divider method of  biasing in amplifiers.

3). Draw the circuit diagram of a push pull amplifier. Explain its operation. Discuss advantages and disadvantages.

4). What do you mean by coupling of two amplifier stages. Explain with requisite circuit  diagrams the resistance-capacitance coupling scheme.

5). Draw the block diagram of negative feed back amplifier. Derive an expression for the voltage gains of an amplifier of gain (A) when subjected to negative feedback (B).

6). Explain the principal of working of transistor Hartley oscillator. Draw circuit diagram and briefly function of each component.

Section-C

7). Define h-parameters. Derive expression for

 (a) Voltage gain (b) Current gain (c) Input resistance

 (d) Output resistance of CE amplifiers using h-parameters

8). (a) Draw labeled diagram showing constructional features of N-channel MOSFET. Explain principle and working of N-channel MOSFET in briefly explain.

      (b) Distortion in amplifier circuits.

9). Write short notes on two of the following:-

 (a) Thermal runway (d) PIN Diodes

 (c) Effect of –ve feed back on output resistance of an amplifier.