Dec = 2007

1 a) i) How many bits are contained the 8 bits ?
ii)What is largest hex number that ca eb represented in 4 bytes ?
iii)What is the largest BCD encoded decimal value that can be represented in a 3 bytes ?
b) Show how to implement an OR gate with NOT and AND gate .

1 c)Perform the following operations .

a) Add +14 to – 17
b) Sub +17 from – 13 .

2 (a) Make a K- map for the function f= AB + AC + C +AD +ABC +ABC
ii)Express f in standard SOP form .
iii)Minimize it and realize the minimized expression using NAND gates only .
b) A multiplier circuit shown th fig takes a 2 bit binary nos y1yo and x1x0 and producres an output nos z3z2z1 that is equal to the arithmatic product of the two inputs nos . Design the logic circuit for multiplier .

3 a)Design a full subtractor using NAND gates only .
b) Inplement the following the function using multiplexer and Decoder .
f(A,B,C,D,E) = Em(0,3,5,6,8,9,10,14,15)

4(a) Explain the working bi – directional shift registers .
(b) Design the 3 bit synchronous UP / DOWN counter using J – Kflip flops .
5 (a) Explain in brief the different characteristics of digital IC's used to compare their performaces .
b)Describe the feature of TTL which make it faster than DTL .
7 a) Compare ROM , PAL & PLA
b) What is FPGA ?Draw the neat diagram and explain the working .
8 (a) CMOS & TTL interface .
b)Dual slope ADC .
c)CPLDs