Digital Logic 2078

Group A

Long Answer Questions.

Attempt any Two questions.     (2x10=20)

1. Design a combinational circuit with four inputs and one output. The output is equal to 1 when (i) all the inputs are equal to 1 or (ii) none of the inputs are equal to 1 or (iii) an odd number of inputs are equal to 1.

2. Implement the following function:

    F = Σ(0,1,3,4,5,8,9,10,15) using

        i) Decoder

        ii) Multiplexer

        iii) PLA

3. What do you mean by race condition in JK Flip Flop and mention the methods to overcome it? Explain Master Slave flip-flop using JK flip flop with logic circuit, truth table and timing diagram. (3+7)

Group B

Short Answer Questions.

Attempt any Eight questions.     (8x5=40)

4. Convert (51966.57)₁₀ into octal and hexadecimal number system.    (2.5+2.5)

5. Subtract (111000.110)₂ - (110100.101)₂ using both 2's and 1's complement.

6. State and prove De-Morgan's Theorems.

7. Define Half-subtractor with truth table and logic diagram.

8. What is decoder? Implement 8 x 1 MUX using 4 x 1 MUX.    (1+4)

9. What is clocked RS flip-flop? Explain with logic diagram and characteristic table.  (1+4)

10. Design Mod-3 synchronous counter.

11. Draw a parallel-In Parallel-Out Shift register and explain it.

12. Write short notes on :    (2.5+2.5)

    a) Binary parallel adder

    b) Jonson counter