Pune University BE Electronics Engineering Electronics System
Design Question Papers
B.E. (Electronic) ELECTRONICS SYSTEM DESIGN (2008 Pattern)
Time :3 Hours] [Max. Marks :100
Instructions to the candidates:-
1) Answer 3 questions from section I and 3 questions from section II.
2) Answers to the two sections should be written in separate answer books.
3) Pigures to right indicate full marks.
4) Use of electronic pocket calculator is allowed.
5) Assume suitable data, if necessary.
SECTION – I
QIA a) Discuss in details different stages of an electronic product development.
Explain the implications of skipping a particular stage in development.  b) Discuss the need for providing redundant hardware in hgih reliability systems. Explain the advantages and disadvantages of redundancy provided. 
Q2) a) Explain the different soldering techniques used in large-scale production and high reliability products. 
b) A communication system is to be designed to work at RF range. Discuss the considerations in design as far as reliability of the system is concerned.
Q3) a) An analog signal conditioning circuitry is to be used for bio medical application; measurement of small differential signal in presence of large common mode noise at high frequencies. Suggest the analog signal conditioning circuitry and discuss factors affecting its choice. 
b) Discuss how ground bounce originates in high-speed circuits and measures taken to limit it. [R]
Q4) a) List different ADC specifications and write their importance from design point of view. 
b) What are different DAC techniques? Compare on the basis of accuracy? 
Q5) For a load cell based weighing machine designed to display weight, rate and price information on display, determine the hardware design considerations and choice of keyboard, display, buses and protocols and microcontroller used. [IT]
Q6) a) What are factors affecting selection of buses and protocols in high speed electronic product. 
b) What are different types of relays and factors affecting selection of it in microcontroller-based circuit? 
SECTION – II
Q7) a) What are features of assemblers and cross compiler. 
b) Explain the different stages in software development at which bugs may enter. List the common bugs and how to overcome these bugs. 
Q8) Write short notes on [IT]
a) Structured programming
b) Real time software
c) Steps in programming assembly code on PC
d) Choice between assembly and high-level language.
Q9) a) Discuss practical cases where following PCB layout practices assume importance 
ii) Component level shielding
iii) Star grounding
iv) Ground loops.
Discuss remedial measures taken to prevent product malfunctioning due to these.
b) A microcontroller circuit is implemented on PCB using FR4 laminate ( sr = 4.1). If at certain location on PCB, the length of two tracks carrying a signal is 12 cm, what should be the maximum clock rise time for which lumped circuit analysis would be valid? [T]
QIO) a) Calculate the characteristic impedance for 
i) Strip line geometry when the PCB laminate thickness is 1.6 mm and relative permittivity is 4.2. The width of embedded track is 1.2 mm and thickness 35 micron.
ii) What would be width of track for micro strip geometry that will result in 60 Q characteristic impedance when the PCB laminate thickness is 1.6 mm and its relative permittivity is 4.3? Assume thickness of track to be 70 micron.
b) Explain different termination schemes for avoiding reflections in highspeed PCB designs. 
QII) a) With the proper examples establish the need for following diagnostic instruments 
i) Analog oscilloscope
ii) Mixed signal oscilloscope
iii) Logic analyzer
b) What different tests are required to be carried out on a product for EMI/ EMC? Discuss different types of EMI and the mechanism by which functioning of electronic product is affected. 
Q22)a) Specify with justification the choice of environmental tests to be carried out on following products: 
i) Washing machine
iii) ECG machine
b) Draw the circuit diagram of transistor LC oscillator and explain how you can make use of DC or operating point analysis and transient analysis to diagnose the circuit.