Hall Ticket No Question Paper Code: AEC006
INSTITUTE OF AERONAUTICAL ENGINEERING
(Autonomous)
B.Tech IV Semester End Examinations (Supplementary) July, 2018
Regulation: IARE R16
PULSE AND DIGITAL CIRCUITS
Time: 3 Hours Max Marks: 70
Answer ONE Question from each Unit
All Questions Carry Equal Marks
All parts of the question must be answered in one place only
UNIT I
1. Draw the output waveform of an high pass RC circuit excited by a square wave input under
different time constants. Derive the expression for percentage of tilt.
Explain the types of series clippers with the neat circuit diagram and transfer characteristics.

2. A square wave is applied to an low pass RC. Draw the output waveforms to scale the following
cases T=RC ii) TRC iii) TRC.
With the neat circuit diagram and waveforms explain the operation of negative clamper.
UNIT II
3. With a neat circuit diagram explain the operation of monostable multivibrator.

Design a bistable multivibrator to meet the following specifications, VCC VBB= 12V, IC(sat)
6mA, hFE 25, maximun triggering frequency 25KHz. Assume VCE(sat) 0.4V,
VBE(sat)= 0.8V, IB(actual) 1.5IB(min).
4. Explain how the astable multivibrator circuit can act as a voltage to frequency converter.
Design a Schmitt trigger circuit using npn transistor for the following specifications VCC 15V,
IC(sat) UTP 8V LTP 5V, hFE(min) 25. Assume 0.5V
UNIT III
5. Explain the effects of control voltage on gate output of a unidirectional diode gate with neat
sketches.
What are the methods of generating time base waveforms. Derive an expression for sweep speed
error of exponential sweep circuit.
6. With the circuit diagram explain the working of transistor boot strap sweep circuit.
Design a UJT sweep circuit with RB1= RB2= 0Ω.The sweep amplitude is to be 10V. The sweep
duration is 1ms sweep speed error is to be and the valley point voltage is 3V. Specify
reasonable values for VBB, VY Y R and C.
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UNIT IV
7. What do you mean by relaxation circuit. Explain the principle of operation of sweep generator
using UJT with neat sketches.
With the help of circuit diagram and waveforms explain frequency division by an astable multivibrator.

8. Describe the method involved in synchronization of a sweep circuit with symmetrical signals with
neat sketches.
With the neat sketch explain the sine wave frequency division with a sweep circuit.
UNIT V
9. Draw and explain the two input TTL NAND gate with totem pole output. What are the advantages
and disadvantages of totem pole.
Draw and explain the operation of ECL OR gate .What are the drawbacks of ECL family.
10. Describe the operation of DTL NAND gate. Clearly mention the purpose served by the diodes
D1 D2. What are the conditions to be fulfilled for the output to be in saturation.
Draw the circuit of CMOS NOT gate and explain its operation . Mention the advantages over
other digital logic families.