Digital Electronics and Design with VHDL

18 Programmable Logic Devices

Chapter Contents

18.1 The Concept of Programmable Logic Devices

18.2 SPLDs

18.3 CPLDs

18.4 FPGAs

18.5 Exercises

Objective:

This chapter describes CPLD and FPGA devices. Owing to their high gate/flip-flop density, wide range of I/O standards, large number of I/O pins, easy ISP (in-system programming), high speed, and decreasing cost, their presence in modern digital systems has grown substantially. Additionally, the ample diffusion of VHDL and Verilog, plus the high quality of current synthesis and simulation tools, also contributed to the wide adoption of such technology. CPLD/FPGA devices allow the development of new products with a very short time to market, as well as easy update or modification of existing ...