IFTM University, Moradabad

B. Tech. (EC) –Semester -IVODD SEMESTER THEORY EXAMINATION 2016

Electronic Circuits-1Time: 03 Hours Total Marks: 70

Note: 1. Attempt any five questions .All questions carry equal marks.

Q1. Obtain the small signal model for common emitter amplifier and also derive an expression for its input impedance, output impedance, voltage gain and current gain.

Q2. Design a voltage divider bias circuit for the specified conditions, VCC=12v, VCE=6v, IC=1mA,

S=20, β=100 and VE=1v.

Q3. The dual input balanced output differential amplifier having Rs=100Ω, RC=4.7KΩ, RE=6.8KΩ, hfe=100, Vcc=+15v and VEE=-15v. Calculate operating point values, differential & common mode gain, CMRR, and output if VS1= 70mV(p-p) at 1 KHz & VS2= 40mV(p-p) at 1 KHz.

Q4. Why biasing is necessary in BJT amplifier? Explain the concept of DC & AC load line with neat diagram. How will you select the operating point, explain it using CE amplifier characteristics?

Q5. Explain the emitter coupled differential amplifier with neat diagram & Derive expression for CMRR.

Q6. Describe the small signal equivalent circuit of the MOSFET and determine the values of small signal parameters?

Q7. Sketch a simple source-follower amplifier circuit and derive the expression of voltage gain.

Q8. Draw the complementary symmetry class B power amplifier and derive its maximum efficiency.

Q9 Mention any two differences between voltage amplifier and power amplifier. Explain how the cross over distortion is minimized.

Q10. Sketch the block diagram of a feedback amplifier and derive the expressions for gain with positive feedback and with negative feedback. State the advantages of negative feedback.

(Following Subject Code and Roll No. to be filled in your Answer Booklet)

Subject Code: EEC-401 Roll No.