Questions - Digital Design Part#1

Here are few question frequently asked in Digital/RTL Design/Verification interviews -

1) Write a FSM (Both Moore and Melay) and draw the Circuit diagram to detect "1010" digital data sequence arriving serially from a signal line?

Ans : Hint - You can use conventional method of using excitation table to draw the circuit diagram but can you think of a simple shift register (Serial input Serial Output) to detect this sequence ? Give a try and lets us know in the comment section !!!




2) What are the difference between Moore and Mealy FSM ? What are the pros and cons of one over the other?

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3) What do you know about the combinational loops in the design ? What are the reasons of generating such loops in the design ? Are they good or bad for the design ?

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4) How combinations loops affects design testing and timings ?

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5) What are the advantages and disadvantages of using one-hot encoding over binary encoding in FSM design ?

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6) Can you list down in how many ways a FSM can be designed ?

Ans: Hint - How will you code for combinational part, sequential part and output logic of a design

7) How many types of shift registers can you think of ? Explain applications of each type ?

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8) Design and implement a MOD3 counter using J-K flip flops ?

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9) Design and implement a MOD5 counter using D flip-flops ?

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10) Draw a circuit for converting a J-K flip flop into a D flip -flop and a S-R flip flop to a J-K flip -flop ? Put your answers in the comment section.

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