Discontinued IC's: Fairchild (?) MB15604; FPGA?

PGA - sometimes it is "Programmable Gate Array" some times "Pin Grid Array" (former is a chip architecture the latter is package type) On the contrary, it is a reaction to that. The first time I was exposed to programmable logic it was with "PAL"s. These are fuse programmed and-or-invert gates tied to an array of interconnects. The term PAL was trademarked by the parent company (whose name escapes me at the moment MMD?, but AMD bought them) and so the generic term was "PLA" (programmable logic array). When the networks within the chip became more complex they weren't really "arrays" anymore and so the generic term for a logic device that could be programmed was "PLD" (programmable logic device). This included memories with programmable chip select logic on chip, and traditional PLAs etc. Erasable devices were called EPLDs. Then "Gate Arrays" became dense enough to be practical and the chips were referred to as "ASICs" (Application Specific ICs) or Gate arrays, or programmed gate arrays (PGAs) but the last was confusing with the package type. Then gate arrays that could be programmed in the field (versus mask programmed) made their debut and they were called Field programmable gate arrays (FPGAs). Devices that were still logic cells that could be combined but had higher densities are called Complex PLDS or CPLDs. --Chuck