Digital Electronics: Principles, Devices and Applications

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Data Conversion Circuits – D/A and A/D Converters

Digital-to-analogue (D/A) and analogue-to-digital (A/D) converters constitute an essential link when digital devices interface with analogue devices, and vice versa. They are important building blocks of any digital system, including both communication and noncommunication systems, besides having other applications. A D/A converter is important not only because it is needed at the output of most digital systems, where it converts a digital signal into an analogue voltage or current so that it can be fed to a chart recorder, for instance, for measurement purposes, or a servo motor in a control application; it is also important because it forms an indispensable part of the majority of A/D converter types. An A/D converter, too, has numerous applications. When it comes to transmitting analogue data, it forms an essential interface with a digital communication system where the analogue signal to be transmitted is digitized at the sending end with an A/D converter. It is invariably used in all digital read-out test and measuring equipment. Whether it is a digital multimeter or a digital storage oscilloscope or even a pH meter, an A/D converter is an important and essential component of all of them. In this chapter, we will discuss the operational fundamentals, the major performance specifications, along with their significance, and different types and applications of digital-to-analogue and analogue-to-digital converters, in addition ...