ABSTRACT
This report provides a survey of architectures of commercially available highcapacity field-programmable logic devices (FPLDs) ex. FPGAs and also the applications of FPGAs. We first define the relevant terminology in the field and then describe the recent evolution of FPLDs. The three main categories of FPLDs are delineated: Simple PLDs (SPLDs), Complex PLDs (CPLDs) and Field-Programmable Gate Arrays (FPGAs). The details of the architectures of the most important commercially available FPGAs are given.
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FPGAs
CHAPTER 1 INTRODUCTION TO HIGH CAPACITY FPLDs
Prompted by the development of new types of sophisticated field-programmable logic devices (FPLDs), 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 mostly of high-density devices. This applies not only to custom devices like processors and memory, but also for logic circuits such as state machine controllers, counters, registers, and decoders. When such circuits are destined for high-volume systems, they have been integrated into high-density gate arrays. However, gate array NRE costs often are too expensive and gate arrays take too long to manufacture to be viable for prototyping or other low-volume scenarios. For these reasons, most prototypes, and also many production designs are now built using FPLDs. The most compelling advantages of FPLDs are instant manufacturing turnaround, low start-up costs, low financial risk and (since programming is done by the end user) ease of design changes. The market for FPLDs has grown dramatically over the past decade to the point where there is now a wide assortment of devices to choose from. A designer today faces a daunting task to research the different types of chips, understand what they can best be used for, choose