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# Digital Logics ### Examination 2019

#### Group B

Attempt any Six question

2. Subtact: 1010.110 - 101.101 using both 2's and 1's complement.

3. Simplify (using k-map) the given Boolen 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.

What is T-Flip Flop? Explain clocked JK Flip-Flop with its logic diagram and truth table.

Design MOD-7 counter with state and timing diagram

#### Group C

Attempt any Two question

9. Define PLA. Design PLA circuit with given funtion.
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
a) Draw the logic diagram.
b) Derive the state table.
c) Derive the state diagram. I there is