Feeding multiple analog sources to one ADC: When several analog inputs need conversion by a single converter, which technique is typically used before the ADC?

Introduction / Context:
Systems frequently must digitize multiple sensor or signal channels with one analog-to-digital converter to save cost and board space. A common front-end strategy selects among inputs rapidly, presenting one signal at a time to the ADC. This question probes the correct term for that selection method.

Given Data / Assumptions:

• There are several analog sources but only one ADC input channel available.
• Channel selection must be electronic, fast, and repeatable.
• The ADC can only sample one input at a time.

Concept / Approach:
The proper technique is multiplexing. An analog multiplexer (often called an analog switch) routes one of many input signals to a single output line under digital control. The ADC then converts that selected signal. Timing is managed so that the selected channel settles within the ADC’s acquisition window before sampling begins.

Step-by-Step Solution:

Verification / Alternative check:
Reference data-acquisition front ends: “MUX + buffer + S/H + ADC” is a standard chain used in multichannel designs, confirming that multiplexing is the go-to approach.

Why Other Options Are Wrong:

Common Pitfalls:
Ignoring settling time and source impedance when switching channels; insufficient settling can cause crosstalk or conversion error.

Final Answer:
multiplexing