Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context: Understanding the distinctions among PROM, PAL, and PLA/FPLA devices helps in selecting the right programmable logic for a given logic function. The key question is which internal planes (AND/OR) are programmable.
Given Data / Assumptions:
Concept / Approach: A PLA (and its field-programmable variant, FPLA) offers flexibility by allowing both product term creation (AND plane) and their combination (OR plane) to be programmed. This supports complex logic sharing and minimizes redundant product terms relative to PALs.
Step-by-Step Solution:
Identify device: FPLA → both arrays programmable.Compare with statement → matches → accurate.Infer design implications: more flexibility, potentially larger area/delay than PAL.Verification / Alternative check:
Textbook block diagrams show programmable fuses/links in both planes for PLAs/FPLAs.Why Other Options Are Wrong:
Incorrect: Opposes standard definition.Only AND programmable: Describes PALs, not PLAs.Only OR programmable: Describes PROMs, not PLAs.Common Pitfalls:
Conflating PAL and PLA capabilities when minimizing logic.Ignoring that flexibility often increases resource usage and timing.Final Answer:
Correct
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