In addition to the two basic functional categories of analog and digital integrated circuits, there are many integrated circuits that have both analog and digital circuitry in the same integrated circuit package, or even on the same chip. Some of the analog integrated circuits mentioned previously, such as the digital-to-analog and analog-to-digital converters, contain both types of circuitry.
The Engineering Handbook 1996, IEEE Press, Article on Analog Integrated Circuits
by Sindey Soclof
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