Demultiplexing concept: A demultiplexer (DeMUX) has which general input/output structure?
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Aone data input and a number of selection inputs, and they have several outputs
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Bone input and one output
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Cseveral inputs and several outputs
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Dseveral inputs and one output
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Etwo data inputs and multiple bidirectional ports
Answer
Correct Answer: one data input and a number of selection inputs, and they have several outputs
Explanation
Introduction / Context:A demultiplexer routes a single data stream to one of many outputs based on select lines. It is the inverse of a multiplexer and is key to signal routing, memory addressing, and time-division systems.
Given Data / Assumptions:
- DeMUX topology: 1 → N routing.
- Select inputs determine which output is active.
- Outputs may be active-high or active-low depending on device family.
Concept / Approach:Recognize the structural definition: a single data input D, k select lines S(k−1:0), and 2^k outputs Y(2^k−1:0) where only one output conveys D at a time.
Step-by-Step Solution:Identify the number of data inputs → one.Account for selection → several select inputs.Outputs → multiple lines (typically 2^k).
Verification / Alternative check:Compare to the multiplexer (MUX) structure which has several data inputs, select lines, and a single output; a DeMUX is the mirror image.
Why Other Options Are Wrong:One input/one output: that is a buffer, not a DeMUX.Several inputs/one output: describes a MUX.Several inputs/several outputs: too vague; not the canonical DeMUX structure.
Common Pitfalls:Confusing select lines with data inputs; select lines choose the destination but are not data channels.
Final Answer:one data input and a number of selection inputs, and they have several outputs