User configurable logic

The article briefly reviews some of the important characteristics of a range of families of programmable logic devices and gives an idea of the complexity of the parts. However, it is only by using the parts in an actual design to be implemented that one gets a true measure of their relative merits. The products considered include: Altera MAX range of logic array blocks (e.g. EP5000 and EP7000 series); Xilinx 2000, 3000 and 4000 CLB series (logic cell arrays with configurable logic blocks); Plessey electrically reconfigurable array, (e.g. ERA60100 and ERA7000 series); Algotronix configurable array logic (e.g. CAL1024); and Actel ACT1 and ACT2 families based on CMOS anti-fuse programming technology