Question

A single-chip data acquisition system incorporates

• A. \( \text{An ADC and a multiplexer} \)
• B. \( \text{An ADC and a DAC} \)
• C. \( \text{A DAC and a demultiplexer} \)
• D. \( \text{An ADC and a demultiplexer} \)

Hint:

Data acquisition systems bridge the analog and digital worlds. When thinking about "single-chip" integration for data acquisition, remember the need to convert real-world analog signals to digital (ADC) and often the need to handle multiple such signals sequentially (multiplexer). This allows for efficient use of a single, often complex, ADC with various input sources.

Answer 1

The Correct Option is A

A data acquisition system (DAS or DAQ system) is used to measure physical phenomena and convert them into digital signals that can be processed by a computer. In many applications, a DAS needs to acquire data from multiple analog sources (e.g., several sensors). A single-chip data acquisition system aims to integrate essential components onto a single integrated circuit to reduce complexity, cost, and size. Let's consider the roles of the components mentioned in the options: \textbullet \ Analog-to-Digital Converter (ADC): This is a core component of any data acquisition system, as its primary function is to convert the analog signals from sensors into digital data. \textbullet \ Multiplexer (MUX): In a system that needs to acquire data from multiple analog inputs, a multiplexer is essential. A multiplexer is a device that selects one of several analog input signals and forwards the selected input into a single output line. This single output is then fed into the ADC. This allows a single ADC to be shared among multiple analog input channels, saving cost and space. \textbullet \ Digital-to-Analog Converter (DAC): A DAC converts digital signals to analog signals. While DACs are crucial in control systems or for generating analog outputs, they are not a primary component for *acquiring* data. They are more relevant for data *output* or reconstruction. \textbullet \ Demultiplexer (DEMUX): A demultiplexer takes a single input and routes it to one of many outputs. It is used for distributing digital signals, not for acquiring multiple analog signals into a single ADC. Considering the function of a data acquisition system to *acquire* data (which implies converting analog to digital) and the common need to handle *multiple* analog inputs on a single chip, the most logical combination for a single-chip data acquisition system is an ADC and a multiplexer. The multiplexer allows selecting different analog input channels to be fed into the single ADC for conversion. Therefore, an ADC and a multiplexer are commonly incorporated in a single-chip data acquisition system.