Difficulty: Easy
Correct Answer: switches logic from one input to any of several output lines
Explanation:
Introduction / Context:
Multiplexers (MUX) and demultiplexers (DEMUX) are fundamental routing elements in digital systems. Knowing the direction of signal selection—many-to-one versus one-to-many—is key when designing data paths, addressing memory banks, or steering control signals.
Given Data / Assumptions:
Concept / Approach:
Demultiplexing distributes a single input to multiple destinations based on select signals. Typical notation: 1-to-N. In contrast, multiplexing is N-to-1. Real devices may combine with latches or tristate drivers in buses; the core logical definition remains the same.
Step-by-Step Solution:
Verification / Alternative check:
Truth tables for 1-to-4 DEMUX show input D appearing at Y0–Y3 depending on select S1:S0, validating the definition.
Why Other Options Are Wrong:
Common Pitfalls:
Confusing DEMUX with decoder; although related, a DEMUX also forwards the data signal, not just asserts a single line.
Final Answer:
switches logic from one input to any of several output lines
Discussion & Comments