A simple, physical demonstration of multiplexing (selecting 1 of N inputs to a single output) can be modeled most clearly using which manual hardware control?
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Asingle-pole relay
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BDPDT (double-pole, double-throw) switch
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Crotary switch (single-pole, multi-throw)
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Dlinear stepper actuator
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Epotentiometer
Answer
Correct Answer: rotary switch (single-pole, multi-throw)
Explanation
Introduction / Context:A multiplexer (MUX) routes one of several inputs to a single output line based on select signals. Demonstrating this concept with tangible hardware helps beginners grasp the selection mechanism before moving to ICs and HDL descriptions.
Given Data / Assumptions:
- Goal: manually emulate choosing 1 of N inputs to one output.
- No need for simultaneous multi-path routing (just one path at a time).
- Emphasis on intuitive, physical analogy.
Concept / Approach:A single-pole, multi-throw rotary switch has one common wiper (the output) and multiple selectable throws (inputs). Rotating the knob selects exactly one input to connect to the output—precisely the behavior of a 1-of-N MUX. DPDT switches route two poles simultaneously and are not a clean 1-of-N model; relays and steppers do not directly illustrate MUX selection.
Step-by-Step Solution:1) Identify MUX behavior: one output, many candidate inputs.2) Map to hardware: the rotary switch wiper corresponds to the MUX output; each throw is an input.3) Selection action: rotating selects one throw at a time, like asserting select lines.4) Therefore, a rotary switch best demonstrates basic multiplexing.
Verification / Alternative check:Electronics labs often use rotary selectors to choose among channels, identical in concept to a 1-of-N selector implemented in silicon.
Why Other Options Are Wrong:Single-pole relay: on/off control, not 1-of-N selection.
DPDT: switches two lines simultaneously, not arbitrary N-way selection.
Linear stepper/potentiometer: not discrete 1-of-N routing devices.
Common Pitfalls:Confusing multi-throw selection with multi-pole switching. A MUX is about choosing exactly one input path to the output.
Final Answer:rotary switch (single-pole, multi-throw)