Page 186 - DCAP108_DIGITAL_CIRCUITS_AND_LOGIC_DESIGNS

Unit 10: Clocked Sequential Circuits

Notes
• The behaviour of a sequential circuit is determined from the inputs, outputs and states of
its flip-flops.
• Analysis is the generation of state table from the given sequential circuit.

10.7 Keywords

Combinational logic: Combinational logic is a type of digital logic which is implemented by
Boolean circuits, where the output is a pure function of the present input only.

Karnaugh map (K-map): A Karnaugh map is a grid-like representation of a truth table. It is really
just another way of presenting a truth table, but the mode of presentation gives more insight.
Sequential logic: Sequential logic is a type of logic circuit whose output depends not only on the
present input but also on the history of the input.
State diagram: A state diagram is a type of diagram used in computer science and related fields
to describe the behaviour of systems.
State table: A state table is the representation of sequence of inputs, outputs, and flip-flop states
in a tabular form.
State minimization: State minimization is the transformation of a given machine into an equivalent
machine with no redundant states.

1. Draw the state diagram of ATM.

2. Draw a logical diagram for sequential circuit.

10.8 Review Questions

1. What are sequential circuits? Explain the circuit diagram.
2. Explain the types of sequential circuits?
3. What is the synchronous sequential circuit?
4. What is a state assignment?
5. Discuss the clocked sequential circuits. And draw the truth table.
6. What is state diagram?
7. How to use K-maps for clocked sequential circuits?
8. What is sequential circuits design?

9. Create a state diagram of the 2-bit binary counter.
10. What is the state minimization?
Answers to Self Assessment
1. (b) 2. (d) 3. (d) 4. (a) 5. (c)

6. (a) 7. (a) 8. (d) 9. (a) 10. (b)

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