Comparator definition — Evaluate: “A device that determines which of two numbers is greater is a comparator.”
Digital Electronics
MSI Logic Circuits
Difficulty: Easy
Choose an option
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ACorrect
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BIncorrect
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COnly true for analog signals
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DOnly true for 8-bit data
Answer
Correct Answer: Correct
Explanation
Introduction / Context: Comparators are used to determine ordering between two inputs. In digital logic, magnitude comparators output signals indicating A>B, A=B, or A
- “Numbers” may refer to digital binary words or analog magnitudes represented as voltages/currents.
- We focus on the core function—establishing greater/less/equal relationships.
- Implementation details (bit width, technology) do not change the definition.
Concept / Approach: A comparator’s essential behavior is to compare two inputs and assert outputs representing relative magnitude. Digital magnitude comparators (e.g., 74×85) produce A>B, A=B, AStep-by-Step Solution:
Identify inputs A and B.Evaluate their magnitudes; hardware sets outputs accordingly.Use the outputs to steer subsequent logic (select max, trigger thresholds, etc.).Verification / Alternative check:
Datasheets and textbooks define comparators by their ability to indicate relative size or threshold crossing.Why Other Options Are Wrong:
Incorrect: Conflicts with standard definitions in both digital and analog domains.Only true for analog signals: Digital comparators exist; the definition is broader.Only true for 8-bit data: Bit width is irrelevant; comparators scale to various widths.Common Pitfalls:
Confusing a comparator with a subtractor; subtractors compute differences, comparators report ordering.Assuming a comparator outputs the larger value; that requires a multiplexer controlled by the comparator.Final Answer:
Correct