In digital design methodology, the initial specification of input–output relationships for a logic function is typically captured using what foundational tabular artifact?
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ATwo-stage
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BStandard
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CTruth
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DTwo-dimensional
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ENone of the above
Answer
Correct Answer: Truth
Explanation
Introduction / Context:Before gates are drawn or HDL is written, designers clarify behavior by enumerating how outputs depend on inputs. This enumeration becomes the seed for simplification, implementation, and verification.
Given Data / Assumptions:
- We are at the specification/derivation stage.
- Inputs are finite, allowing exhaustive listing.
- The goal is a deterministic combinational function mapping inputs to outputs.
Concept / Approach:A truth table lists all input combinations and the corresponding outputs. From it, Karnaugh maps or Boolean algebra can be used to minimize logic and derive gate-level or HDL implementations.
Step-by-Step Solution:
Define inputs: e.g., A, B, C (n bits → 2^n rows).Enumerate all combinations and specify outputs Y.Use the table to extract minterms/maxterms and simplify.Verification / Alternative check:Cross-check with simulation: implementing the simplified logic must reproduce the truth table for all rows.
Why Other Options Are Wrong:
- Standard/Two-stage/Two-dimensional: imprecise or descriptive terms, not the accepted artifact name.
- None of the above: incorrect because 'Truth' (truth table) is correct.
Common Pitfalls:Skipping impossible input combinations; failing to specify don't-cares; mislabeling bit order leading to logic errors downstream.
Final Answer:Truth