Tribhuvan University
Bachelor of Computer Application
Semester 1 · TU Board 2024
Course Title: Digital Logic (CACS103)
Full Marks: 60Pass Marks: 24Time: 3 hours
Candidates are required to answer the question in their own words as far as possible.
Group B
Attempt any SIX question.(6 × 5 = 30)
- 4.5
Differentiate between combinational and sequential logic circuits. Implement a full adder circuit using a decoder and two OR gates.
- 5.5
Define priority encoder. Explain 8-to-3 priority encoder in detail.
- 6.5
Explain the duality theorem with an example. Draw logic gates that implement the expression:
- 7.5
How does a flip-flop differ from a latch? Explain clocked SR flip-flop with logic diagram, truth table, characteristic table, and excitation table.
Answer comingAlso asked in 2021, 2020, 2019, Model question
- 8.5
Write short notes on (any two): a) State reduction table b) Multiplexe c) Synchronous and Asynchronous counter
Group C
Attempt any TWO questions(2 × 10 = 20)
- 9.10
Differentiate between PAL and PLA. Design a combinational circuit with four inputs (BCD digit) and four outputs lines that generate the 2'Complements of the binary input pattern with circuit diagram, truth table, and block diagram.
- 10.10
Explain shift register with parallel load. Design a synchronous Mod-10 counter to count in the sequence 0,2,4,5,6,8 using T flip-flops.
- 11.10
Explain how race condition in JK flip-flop can be resolved. A sequential circuit with two D Flip-Flops (A, B), inputs , and output is defined by:
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