NMOS logic capability: Do NMOS logic families implement arbitrary logic networks (since NAND is a universal gate), using MOSFETs to realize the full range of logic functions?

Introduction / Context:
Before CMOS dominated, NMOS logic was widely used in microprocessors and standard logic. Theoretically, certain gates are universal, meaning any Boolean function can be constructed from them. This question checks recognition that NMOS can realize complete logic via MOSFET networks.

Given Data / Assumptions:

• NMOS uses n-channel MOSFET pull-down networks with resistive or active pull-ups.
• NAND and NOR are universal gates in Boolean algebra.
• Practical considerations (power and noise) are separate from functional completeness.

Concept / Approach:
Universality: any Boolean function can be built from NAND alone or NOR alone. NMOS technology can implement NAND/NOR using series/parallel nMOS networks and a pull-up device. Therefore, NMOS can realize arbitrary logic despite different performance characteristics versus CMOS.

Step-by-Step Solution:

Verification / Alternative check:
Historic NMOS CPUs (e.g., early microprocessors) demonstrate complex logic realized entirely in NMOS, confirming functional completeness.

Why Other Options Are Wrong:

• “Only inverters and NOR” understates capability; NAND/NOR/inverters suffice for completeness.
• “Only CMOS can realize complete logic” is false in Boolean terms.
• “Requires bipolar devices” confuses device physics with logic algebra.

Common Pitfalls:
Equating functional completeness with optimal power efficiency; NMOS has static power draw with resistive pull-ups, which is why CMOS replaced it for mainstream logic.

Final Answer:
Valid — NMOS can implement arbitrary logic because NAND/NOR are universal.