$($a$)$ Briefly answer the following questions:

Identify the difference between ripple$-$carry adder and carry look

ahead adder circuits. Describe any reason why a ripple$-$carry adder

takes more time to add as compared with a carry look$-$ahead adder.

Determine a BCD representation for $(17,000{)}_{10}$ number. Justify

your answer.

$(6$ marks$)$

Question #$2$ continues on Page $3$

Page $2$ of $7,04-$BS$-8,$ December $2016$

$($b$)$ Determine the number of gates required to implement a $4-$bit ripple$-$

carry adder. Use AND, OR and XOR gates only with any number of

inputs.

$(9$ marks$)$

$($c$)$ Show how function $F$ can be implemented using minimum number of

NAND gates only. Show your complete work related to combinational

logic simplification such as K$-$maps, etc.

$F(w,x,y,z)={\displaystyle \underset{?}{\overset{?}{}}}m(0,2,3,5,6,13)$

$(10$ marks$)$