Chapter 2 - FPGA Fundamentals

Abstract

This chapter provides an overview of the fundamental of field-programmable gate arrays (FPGA), programmable logic technology (PLD), and the factors that affect PLD technology selection. The three PLD categories include simple programmable logic devices (SPLDs), complex programmable logic devices (CPLDs), and field programmable gate arrays (FPGAs). The crossover between CPLD and FPGA applications is discussed in the chapter. CPLDs and FPGAs are optimized to implement the similar but different ranges of functionality efficiently because of their architectural characteristics. CPLDs are well suited to combinatorial functions with limited register requirements, while FPGAs can implement larger, more register-intensive functionality. The primary focus of this chapter is on rapid design implementation with FPGA technology. The primary types of FPGAs and major FPGA manufacturers are presented in the chapter. The main FPGA categories are one-time programmable (OTP) and static random access memory (SRAM)-based. As SRAM-based FPGAs are typically better suited for rapid system prototyping, special attention is focused in the chapter on the architecture of SRAM-based FPGAs. The fundamental FPGA structures presented in the chapter include the configurable logic block and slice, routing matrix, global signals, I/O blocks, clocking resources, and memory.