Architecture of FPGAs and CPLDs: A Tutorial

This paper provides a tutorial survey of architectures of commercially available high-capacity field-programmable devices (FPDs). We first define the relevant terminology in the field and then describe the recent evolution of FPDs. The three main categories of FPDs are delineated: Simple PLDs (SPLDs), Complex PLDs (CPLDs) and Field-Programmable Gate Arrays (FPGAs). We then give details of the architectures of all of the most important commercially available chips, and give examples of applications of each type of device. Page 2 of 41 1 Introduction to High-Capacity FPDs Prompted by the development of new types of sophisticated field-programmable devices (FPDs), the process of designing digital hardware has changed dramatically over the past few years. Unlike previous generations of technology, in which board-level designs included large numbers of SSI chips containing basic gates, virtually every digital design produced today consists mostl