7.7 INTRODUCTION TO FPGAS AND OTHER GENERAL-PURPOSE DEVICES 317
7.7 INTRODUCTION TO FPGAs AND OTHER GENERAL-PURPOSE DEVICES
The devices briefly discussed in this section vary in size from SSI to LSI circuit modules and
range greatly in complexity from simple gate-level modules to those having a multiplicity of
components, including flip-flops. Of the general purpose devices, the simplest are the AND–
OR–invert or OR–AND–invert type devices with logic equivalent gate counts numbering
typically in the three to five range. These SSI circuits are often used as building blocks in
complex logic devices. Then, within the PLD spectrum of devices, the most complex class
belongs to the field programmable gate array (FPGA) devices, which may contain a variety
of