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
Given Data / Assumptions:
- “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, A
Step-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
Discussion & Comments