The two major types of programmable logic devices are field programmable gate arrays (FPGAs) and complex programmable logic devices (CPLDs). Of the two, FPGAs offer the highest amount of logic density, the most features, and the highest performance. The largest FPGA now shipping, part of the Xilinx Virtex™ line of devices, provides eight million "system gates" (the relative density of logic). These advanced devices also offer features such as built-in hardwired processors (such as the IBM Power PC), substantial amounts of memory, clock management systems, and support for many of the latest, very fast device-to-device signaling technologies. FPGAs are used in a wide variety of applications ranging from data processing and storage, to instrumentation, telecommunications, and digital signal processing.
CPLDs, by contrast, offer much smaller amounts of logic - up to about 10,000 gates. But CPLDs offer very predictable timing characteristics and are therefore ideal for critical control applications. CPLDs such as the Xilinx CoolRunner™ series also require extremely low amounts of power and are very inexpensive, making them ideal for cost-sensitive, battery-operated, portable applications such as mobile phones and digital handheld assistants
