Page 86 - Computer science 868 Class 12
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4. NAND and NOR are called ………………… gates.
5. ………………… is a unary gate.
6. The sum term of a Half adder is equal to a two-variable ………………… gate.
7. Encoder converts any Octal , Decimal or Hexadecimal number to its ………………… form.
8. Multiplexer is called a data ………………… .
9. ………………… converts binary number to its Octal, Decimal or Hexadecimal form.
10. A MUX has 2n selection lines , n input lines and ………………… output lines.
Answers
1. (A.B)' 2. XNOR 3. 2 4. universal 5. NOT
6. XOR 7. Binary 8. selector 9 Decoder 10. 1
C. Answer the following questions:
1. Draw the logic circuit diagram of the following Boolean expression using AND, OR gates. Assume complement is available as
input.
(i) (B'+D).(A'+D').(B+C'+D') (ii) (B'.C'+A.C)'
Ans. (i) (ii)
B' (B'+D) B' B'.C'
D C' (B'.C' + A.C)'
(B'+D).(A'+D').
A' (A'+D') (B+C'+D')
A
D'
C A.C
B
C'
D' (B+C'+D')
2. Draw a logic circuit diagram to represent AND, OR and NOT gates using NOR gate only.
Ans. (i) NOT gate using NOR gate
A (A+A)' A'
A
(ii) OR gate using NOR gate
A (A+B)' (A+B)
B
(iii) AND gate using NOR gate
A A'
A
A.B
B B'
B
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