Inside a simple PLD The internal content and programmability of a simple programmable logic device (PLD) are best described as which of the following?

Introduction / Context:
Before large FPGAs, designers used simple PLDs—PALs, GALs, and small CPLDs—for glue logic and control. Knowing what is actually programmable inside these devices clarifies their capabilities and limitations versus gate arrays and modern FPGAs.

Given Data / Assumptions:

• “Simple PLD” refers to classic PAL/GAL-style devices, not high-density FPGAs or complex CPLDs.
• Programming technology historically uses fuses, antifuses, EPROM/EEPROM, or flash to configure connections in the AND (and sometimes OR) plane.
• They do not literally contain thousands of discrete gates like a gate array.

Concept / Approach:
Simple PLDs implement logic by selectively connecting input signals (and their complements) to product-term lines through programmable links (fuses, floating gates, etc.). The resulting AND terms feed a fixed OR plane and macrocells. Hence, the essence of programmability lies in the array of programmable interconnect links, not a sea of individually addressable gates or complex sequential macros by default.

Step-by-Step Solution:

Verification / Alternative check:
Manufacturer block diagrams and programming algorithms (for example, JEDEC fuse maps) directly show arrays of programmable links.

Why Other Options Are Wrong:

• thousands of gates / advanced sequential logic: Describe gate arrays or FPGAs, not simple PLDs.
• Combination of both: Overstates capabilities beyond “simple” PLDs.

Common Pitfalls:
Equating CPLDs/FPGAs with simple PALs and expecting large embedded sequential feature sets.

Final Answer:
fuse-link arrays