VLSI Design - May 2017

MU Electronics and Telecom Engineering (Semester 6)

Total marks: --
Total time: -- INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary

Solve any four question from Q.1(a, b, c,d, e)

1(b) Implement the following function using Dynamic CMOS logic $$Y=\overline{A(B+C)}$$<script type="math/tex; mode=display" id="MathJax-Element-1"> Y=\overline{A(B+C)}</script> 5 marks

1(c) Compare Ripple carry adder with CLA. 5 marks

1(d) Explain working principle of flash memory. 5 marks

1(e) Explain importance of low power design. 5 marks

2(a) Compare the full scalling & constant voltage scalling models of MOSFET Demonstrate the effect of scalling on the area, delay, power consumption and current density of the device. 5 marks

2(b) Expalin transfer characteristic of NMOS inverter showing different regions, what is the effect of variation in W/L ratio? 5 marks

3(a) Draw 1T DRAM cell and explain it's write read hold & refresh operation. 5 marks

3(b) Explain scheme for multiplication on 101*010. 5 marks

4(a) Explain various techniques of clock generation & clock distribution . 5 marks

4(b) Consider a CMOS inverter circuit with following parameters
V_DD=3.3v.
V _To.n = 0.6v.
V _{To.p = 0.7v
Kn = 200μ A/v²
Kp= 80 μ A/v²
Calculate noise Margins of the circuit Consider KR = 2.5 & V To.n ≠V ro.p} 5 marks

5(a) Draw JK Flip Flop using CMOS and explain the working. 5 marks

5(b) Draw CLA ( carry look head adder) carry chain using dynamic CMOS logic. 5 marks

Write short note any three question from Q.6(a,b,c,d)

6(b) Sense Amplifier 5 marks

6(c) Interconnect scaling. 5 marks

6(d) 4*4 Barel shifter. 5 marks