Identifying the PAL structure A device that consists of a programmable array of AND gates feeding a fixed array of OR gates, and that is usually one-time programmable (OTP), is called a:

Introduction / Context:Programmable logic devices come in many architectural flavors. Two historically important types are PALs and GALs. PALs generally provide a programmable AND plane and a fixed OR plane, while GALs add reprogrammable technology and versatile output macrocells. Understanding the architectural hallmark of a PAL helps you recognize its capabilities and limitations.

Given Data / Assumptions:

• Structure: programmable AND array, fixed OR array.
• Programming model: typically one-time programmable (fuse/OTP).
• Target: choose the device class that best matches the structure and OTP behavior.

Concept / Approach:

The defining characteristic of a PAL (Programmable Array Logic) device is exactly this sum-of-products organization with a programmable AND matrix and fixed OR summation. Many PALs were OTP, distinguishing them from later GALs that used erasable technologies (e.g., EEPROM) and offered per-pin OLMC flexibility.

Step-by-Step Solution:

Verification / Alternative check:

Historical datasheets and textbooks present classic PAL block diagrams showing an AND matrix with fixed OR gates driving outputs, sometimes with simple output enable/inversion controls.

Why Other Options Are Wrong:

GAL: similar purpose but reprogrammable with more flexible OLMCs.

CPLD: multi-macrocell blocks with wider interconnect; not necessarily fixed OR planes as in classic PALs.

SPLD: a generic category that includes PAL and GAL; not specific enough to match the exact description.

Common Pitfalls:

Confusing the general SPLD category with a specific architecture. Here the exact structure and OTP cue point to PAL.

Final Answer:

PAL