12 - Integrated circuit design

Abstract

The difficulty involved in designing large integrated circuits has grown far beyond the capabilities of a purely manual approach. The successful completion of a large circuit necessitates both a highly structured design methodology and computer-aided support. The very large scale implementation (VLSI) design process can be viewed as a sequence of transformations, starting with a functional or behavioral description of the system at the logic level and ending with a geometric description that can be used for manufacturing the circuit. This process is inherently very complex and involves large amounts of design information. A structured approach is mandatory not only to cope with the high complexity, but also to reduce the amount of design data. Generally, a structured design approach aims at a highly modular and regular design that is partitioned into small, noninteracting parts that are easy to design. Design complexity is reduced if the modules can successively be partitioned (assembled) into smaller (larger) modules without too much effort. The complexity and the amount of design data are further reduced in regular design since such a design has only a few types of modules. Standardization reduces the probability of errors and provides a basis for the design tools. Moreover, a hierarchy of well-defined modules provides a necessary framework for automatic design tools.