Logic Gates — Understanding the NAND Function A standard NAND gate is the inversion of an AND gate. Considering conventional (active-HIGH) logic signaling, which description best matches the input sense and the output sense of a NAND gate?

Introduction / Context:
A NAND (Not-AND) gate is one of the fundamental building blocks in digital electronics. It outputs the logical complement of the AND function. Understanding what “active-HIGH inputs” and “active-LOW output” mean clarifies how NAND behaves in truth tables, logic design, and real circuits.

Given Data / Assumptions:

• Conventional binary logic with logic 1 = HIGH voltage and logic 0 = LOW voltage.
• NAND implements Y = NOT(A * B * ...), where * denotes logical AND.
• “Active-HIGH input” means a logic 1 is the asserted/true state for the input.
• “Active-LOW output” means the output asserts (true condition) as a LOW level in response to the input condition being met.

Concept / Approach:
The AND gate produces HIGH only when all inputs are HIGH. The NAND gate inverts that result, producing LOW only when all inputs are HIGH. Thus, the inputs are interpreted in the normal active-HIGH sense, and the output is LOW (active-LOW) in the unique case that all inputs are asserted.

Step-by-Step Solution:
1) Consider an AND gate: for inputs A, B, the output is A * B.2) Invert that to obtain NAND: Y = (A * B)' = NOT(A * B).3) With active-HIGH inputs, the “all-ones” condition (A = 1 and B = 1) makes AND = 1.4) NAND then produces Y = 0 only in that condition; otherwise Y = 1.5) Therefore, inputs are active-HIGH, and the asserted condition at the output is a LOW (active-LOW) when all inputs are HIGH.

Verification / Alternative check:
Truth table: 00→1, 01→1, 10→1, 11→0 for 2-input NAND. The output is LOW exactly when both inputs are HIGH, matching the “active-HIGH inputs, active-LOW output” description.

Why Other Options Are Wrong:

• active-LOW inputs and an active-HIGH output: Inputs are not interpreted as active-LOW for a standard NAND symbol.
• active-LOW inputs and an active-LOW output: Double mismatch with standard logic interpretation.
• active-HIGH inputs and an active-HIGH output: Describes an AND gate, not NAND.

Common Pitfalls:
Confusing AND with NAND; overlooking that “active-LOW output” simply means the output’s asserted condition is LOW (the bubble at the output in logic symbols).

Final Answer:
active-HIGH inputs and an active-LOW output.