Definition check What does the acronym PROM stand for in digital electronics?

Introduction / Context:
PROM is a foundational nonvolatile memory component used to store fixed data such as lookup tables and firmware. Understanding the definition distinguishes memory devices from programmable logic devices (PLDs) like CPLDs and FPGAs, which implement arbitrary logic rather than just storing data patterns.

Given Data / Assumptions:

• PROM is a memory device acronym encountered in digital systems courses and datasheets.
• We seek the full expansion and meaning of the acronym.
• No vendor-specific nuance is required; standard textbook definition applies.

Concept / Approach:
PROM expands to Programmable Read-Only Memory. It is manufactured blank and then permanently programmed once (for example, by burning fuses). Variants include EPROM (erasable with ultraviolet light), EEPROM/Flash (electrically erasable). PROM is not a PLD; it stores data rather than configurable gate interconnects. Its output is determined solely by address inputs, not by combinational networks synthesized from HDL.

Step-by-Step Solution:

Verification / Alternative check:
Introductory digital design texts define PROM as a one-time programmable nonvolatile memory, confirming the expansion and meaning.

Why Other Options Are Wrong:

• Programmable Logic Device: A broader class (PLD), not a memory acronym.
• Polarized Readout Module / Peripheral Register and Output Matrix: Fabricated distractors, not standard terminology.

Common Pitfalls:
Assuming all programmable devices implement logic (confusing PROM with PLD). PROM stores static data; it does not provide the flexible routing and LUT fabric of FPGAs or the product-term arrays of PALs/GALs.

Final Answer:
Programmable Read-Only Memory