Digital Logic 2072
Long Questions:
Attempt any two questions: (2 × 10=20)
1. Design and implement with logic diagram of synchronous 3 bit up down counter using J-K flip flop.
2. Design a magnitude comparator using logic gates and truth table.
3. Design a master-slave S-R flip flop with logic diagram and truth table.
Short Questions:
Attempt any eight questions: (8 × 5=40)
4. What do you mean by the Gray code? What are its application?
5. Covert the following:
a) A08E. FA16 = (? )10
b) AE9. BOE16 = (? )2
6. State and prove commutative laws, associative laws and distributive law using logic gate and truth table.
7. Show that both NAND gate and NOR gate are universal gates.
An universal gate is a gate which can implement any Boolean function without need to use any other gate type. The NAND and NOR gates are universal gates.
NAND gate
NAND gate is the combination of NOT gate and AND gate. If the two input values for an NAND gate are both 1, the output is 0; otherwise, the output is 1.
Fig: Various representations of a NAND gate
NAND gate as a Universal Gate
To prove that any Boolean function can be implemented using only NAND gates, we will show that the AND, OR, and NOT operations can be performed using only these gates.
Thus, the NAND gate is a universal gate since it can implement the AND, OR and NOT functions.
NOR gate
NOR gate is the combination of NOT gate and OR gate. If the two input values for NOR gate are both 0, the output value is 1; otherwise, the output is 0.
Fig: Various representations of a NOR gate
NOR gate as a Universal Gate
To prove that any Boolean function can be implemented using only NOR gates, we will show that the AND, OR, and NOT operations can be performed using only these
Thus, the NOR gate is a universal gate since it can implement the AND, OR and NOT functions.
8. Prove that:
9. Reduce the following expression using K-map.
10. How does a J-K flip flop differs from an S-R flip flop in its basic operations? Explain.
11. Differentiate between a counter a shift register.
12. Design a 4 input multiplexer using logic diagram and truth table.
13. Explain the serial-In, parallel out shift register.