A demultiplexer is used to :

Question

Question

This question was previously asked in

NIELIT Scientific Assistant CS 5 Dec 2021 Official Paper

Answer 1

The correct answer is: Option 3) Both (1) and (2)

Key Points

Demultiplexer (Demux) is a combinational logic circuit that takes a single input and routes it to one of many outputs.
This routing is done based on the values of select lines, which decide the active output line.
Function 1 – Routing: It is commonly used in scenarios where you want to distribute or route data from a single source to multiple destinations — e.g., in data distribution systems.
Function 2 – Serial to Parallel Conversion: A demultiplexer can also be used in serial to parallel data conversion. Each time a new bit arrives (serial input), it is sent to a different output (like storing each bit in a different register), hence building a parallel word over time.

Additional Information

Example: A 1-to-4 demux has 1 data input, 2 select lines, and 4 outputs. Depending on the values of the select lines (00, 01, 10, 11), the input is routed to Y₀, Y₁, Y₂, or Y₃.
Use Case in Microprocessors: Demultiplexers are used to control and direct address or data signals from the processor to multiple memory or peripheral devices.
Therefore, the demultiplexer’s behavior aligns with both routing (Option 1) and serial to parallel conversion (Option 2), making Option 3 the correct answer.