Chapter 6 - Digital Circuits

Abstract

Publisher Summary The success story of digital electronics is due to one simple fact: information can be reduced to a stream of binary data that can be represented as one of two discrete voltage levels. This data can be manipulated and processed at will, and the quantity of information that can be processed depends only on the speed at which it is done. The infinite variability of analogue voltage levels is replaced by two dimensions of quantization—voltage and time. In theory, all voltage levels below a given threshold represent binary 0, and all levels above the threshold represent binary 1. Time is divided into discrete units by a reference clock, and the boundary between each unit marks the transition from one bit of data to the next. The unpredictability and variability of analogue, or linear, electronic phenomena is factored out of the design process. Voltage drift, component tolerances, offsets, and impedance inaccuracies become instantly irrelevant. Programmability allows a single piece of hardware to perform widely different tasks. To incorporate such programming flexibility into analogue hardware would be impossible. The millions of successful digital designs worldwide testify to these advantages.