WBJECA 2025 — Computer PYQ
WBJECA | Computer | 2025Which of the following best distinguishes a sequential circuit from a combinational circuit?
Choose the correct answer:
- A.
Sequential circuits produce output based only on current inputs.
- B.
Sequential circuits use both current inputs and past states to determine output.
(Correct Answer) - C.
Combinational circuits have memory elements to store past states.
- D.
Combinational circuits require a clock signal to operate.
Sequential circuits use both current inputs and past states to determine output.
Explanation
Explanation:
The primary distinction between these two circuits lies in the presence of memory.
Combinational Circuits: The output depends solely on the current input values. They do not possess any storage capacity, meaning they cannot "remember" past events.
Mathematically, this can be represented as:
Output=f(Current Input)
Sequential Circuits: These circuits include memory elements (like flip-flops or latches). Consequently, their output is a function of both the current inputs and the past state (history) of the circuit.
Mathematically, this is represented as:
Output=f(Current Input,Previous State)
Therefore, option (B) accurately captures the defining characteristic that separates sequential logic from combinational logic. Options (A), (C), and (D) incorrectly describe the functional requirements or behaviors of these circuits.