Definition check: A ________ is a combinational circuit that compares two binary quantities and asserts outputs indicating which operand has the greater magnitude (greater-than, equal-to, or less-than).

Introduction / Context:
Digital systems frequently need to determine ordering between two numbers—for sorting, branching, or implementing conditional operations. Dedicated combinational circuits are designed to perform this comparison efficiently at the hardware level.

Given Data / Assumptions:

• Two binary inputs of equal width.
• Three outputs representing P>Q, P=Q, P
• Purely combinational operation, no clock.

Concept / Approach:
A magnitude comparator examines corresponding bits (often from MSB to LSB). If a mismatch is found at some position, the higher bit determines which operand is larger. If all bits match, the equal output is asserted. Standard ICs like the 7485 implement this logic and can be cascaded to handle wider words by feeding carry-in-like cascade inputs/outputs.

Step-by-Step Solution:

Verification / Alternative check:
Truth tables show exactly one output active for each input pair; logic simulations confirm the one-hot behavior across all combinations.

Why Other Options Are Wrong:

• demultiplexer: Routes one input to many outputs; it does not compare values.
• code converter: Maps codes between formats (e.g., BCD to 7-seg), not comparisons.
• E-MOS: A transistor technology term, not a logic function block.

Common Pitfalls:
Assuming subtraction is required; while subtraction can be used internally, comparators are optimized logic networks that avoid full arithmetic where unnecessary.

Final Answer:
magnitude comparator