DIGITAL LOGIC DESIGN
OBJECTIVE QUESTIONS
UNIT-1
1. What is the binary equivalent of the
decimal number 368 [ B
]
A) 110110000 B) 101110000 C) 111100000
D) 111010000
2. The code where all successive numbers
differ from their preceding number by single bit is [ D ]
A) Binary Code B) BCD C) Excess-3 D) Gray
3. -8 is equal to signed binary number [
B ]
A) 00001000 B) 10001000 C) 10000000 D) 11000000
4. The 9’s Compliment of 546700 is [
B ]
A. 435299 B. 453299 C. 432599 D. 425399
5. Which of the following are called
Universal gates [ B ]
A) NAND, NOR B) AND, OR
C) XOR XNOR D) OR, XOR
6. x+y=y+x is the [
A ]
A) commutative property B)inverse
property C) associative property D) identity element
7. The decimal equilent of the binary
number 101101 is [ B ]
A) 48 B)45 C)57
D)75
8. The number of bits required to represent
ASCII code of a Character is --[A]
A)
7 B) 2 C) 4
D) 6
9. Convert binary 101011110010 to
hexadecimal. [ D ]
A) EE2 (16) B) FF2 (16) C) 2FE (16) D) AF2 (16)
10. Gray Code of the binary number
111001010 is [A]
A) 100101111 B) 100001001 C) 11110010 D) 100111001
11.When the set of input data to an even
parity generator is 0111, the output will be
1
12. Signed 2’s complement representation of
decimal number of -17 by using 8 bit representation is 11101111
13.When simplified with Boolean Algebra (x
+ y)(x + z) simplifies to x+yz
14.
(x’)’ is x
15. Not gate is also known as inverter
16.
10's complement of the decimal number 3750 is 6250
17.
In Ex-NOR truth table, output for input combination of 1 and 0 is
__________________.
18. In Boolean Algebra A+AB is = A
19. The given expression Y=A+AB+ABC in
Canonical form is ABC+ABC'+AB'C+AB'C'
20.The most common error detecting code
used is called parity bit
UNIT-2
1. Karnaugh map is used for the purpose of [C]
A) Reducing the electronic circuits
used. B) To map the given Boolean logic
function.
C) To minimize the terms in a Boolean
expression. D) none
2.The canonical form of Boolean Function
f(x,y,z) = xy + yz’x is [C ]
A) xyz + yz’x’ B) xyz + yz’ C) xyz + xyz’ D) xyz + 2xyz’
3. The output levels which are indicated by
‘X’ or ‘d’ in the truth tables are called
[D]
[D]
A) Dont care outputs B) Dont care conditions C)
incompletely specified functions
D) All of the above
4.Boolean functions expressed as a Sum of
minterms or Product of maxterrms are said to be in
[ D]
[ D]
A. Product terms B. Sum terms C. Standard form D. Canonical form
5.
Combining the maximum possible no of adjacent squares in a map is
called
[ C ]
[ C ]
A) Odd implicant B) Even implicant C)Prime implicant D) Integer
implicant
6. The code for labelling the cells of the
K map is ______ [C]
A)BCD B)Hexadecimal
code C)Gray D)Octal
7.The implementation of a boolean function
with NAND-NAND logic requires that the function be
simplified in ___________________ [B
]
A)POS B)SOP C)both a and b D)none
8. In K Map
Don't care Conditions marked by ____[C]
A)1 B)0 C)X
D)all
9. What is group of four adjacent 1's 0r
0's called _ [B]
A) pair B)Quad C)Octet
D) None of these
10. Any logical expression can be realized
by using only____[ D ]
A)AND gates B)OR gates C)NOT gates D)NAND or NOR gates
11.T
he simplified expression for the function F 1 = f(A,B,C) = (2,3,7) is A'B+BC
simplified in POS
13. Simplify the three variable expression
y=∑m(1,3,5,7) gives C
14.SEQUENTIAL CIRCUITS are the circuits whose output
variables at any instant of time are dependent not only on the present input variables, but
also on the previous outputs variables.
15. The Number of NAND gates required to
realize EX-OR gate is 4
16. NAND – NAND Realization is equivalent
to AND-OR REALIZATION
17. The logic function which is produced by
adding an inverter to each input and output of an AND gate is OR
18. Three variable will be represented by 8
minterms
19. The prime implicant which has at least
one element that is not present in any other implicant is known as Essential Prime Implicant
20.The number of cells in a 5 variable
K-map is 32
