ABSTRACT
This chapter provides a brief overview of analogue data and analogue input and output subsystems which generally known as analogue data acquisition systems. Analogue data is data that can have any one of an infinite number of values within some range. In the market now, many microcontrollers and microprocessors have on chip a built-in analogue to digital converters with all the needed interface circuitry. In an analogue input subsystem, the purpose of signal conditioning is to provide the analogue-to-digital converter (ADC) with a noise free signal compatible with its input range. Amplification and filtering are the most commonly required signal conditioning operations. The ADC then converts the output voltage of the track-hold. In the multichannel data acquisition system, an analogue multiplexer is used to select an analogue input for conversion. Analogue-to-digital converters and digital-to-analogue converters provide the fundamental interface between analogue and digital signals.
