Digital Logic 2019 - BCA (TU) Old Questions
Group B
Attempt any Six question
2. Subtract: 1010.110 - 101.101 using both 2's and 1's complement.
3. Simplify (using k-map) the given Boolean unction in both SOP and POS using the don't case condition d:
f(A,B,C,D)=π(0,1,3,7,8,12) πd (5,10,13,14)
4. Define decoder. Draw logic diagram and truth table of 3 to 8-line decoder.
5. Define ROM. Implement the following combinational logic function using ROM:
| A1 | A0 | F1 | F2 |
| 0 | 0 | 1 | 0 |
| 0 | 1 | 0 | 1 |
| 1 | 0 | 1 | 1 |
| 1 | 1 | 1 | 0 |
6. What are the drawbacks of clocked RS Flip Flop? Explain the operation of JK Flipflop along with its circuit diagram and characteristic table.
7. What is T-Flip Flop? Explain clocked JK Flip-Flop with its logic diagram and truth table.
8. Design MOD-7 counter with state and timing diagram
Group C
Attempt any Two question
9. Define PLA. Design PLA circuit with given funtions.
F1(A,B,C)=Σ (3,5,6,7)
F2(A,B,C)=Σ (0,2,4,7).
Design PLA Program table also
10. Distinguish between sequential and combinational logic with example? Discuss the design procedure of combinational logic.
11. A sequential circuit with two D flip flops, A and B, two inputs x and y, and one output z, us specified by the following next state and output equations.
A(t + 1)=x'y + xA
B(t + 1)=x/B + xA
z=B
- Draw the logic diagram.
- Derive the state table.
- Derive the state diagram.