🎛️ Multiplexer

A multiplexer (MUX) is a digital logic device that selects one input from many and routes it to a single output, based on control signal called a selector

The multiplexer itself can be thought of as a “selector”, although the one that actually selects the output is within the multiplexer

    graph TD
  subgraph Inputs
    I0["I₀"]
    I1["I₁"]
    I2["I₂"]
  end

  subgraph Select Lines
    S0["S₀"]
    S1["S₁"]
  end

  subgraph Multiplexer
    MUX["MUX (4-to-1)"]
  end

  subgraph Output
    Y["Output Y"]
  end

  I0 --> MUX
  I1 --> MUX
  I2 --> MUX
  S0 --> MUX
  S1 --> MUX
  MUX --> Y
  

• Inputs: $n$ binary signals
• Output: 1

ℹ️

Notes MUX is often called a data selector.

Can be built using logic gates or hierarchical MUX trees.

In programming, MUX behavior resembles a switch-case or if-else chain

⚙️ Applications

• Data routing and bus control
• Function selection in ALUs
• Signal switching in communication systems
• Logic minimization and conditional operations