FPLAs

FPLAs, or Field Programmable Logic Arrays, are integrated circuits designed to be configured by a customer or designer after manufacturing. This "programmability" allows the same FPLA chip to perform a wide variety of digital logic functions, making them highly flexible and cost-effective for prototyping and low-to-medium volume production. Unlike dedicated application-specific integrated circuits (ASICs), FPLAs do not require expensive and time-consuming mask reprogramming.

The fundamental structure of an FPLA consists of a programmable array of AND gates and a programmable array of OR gates. Input signals are routed to the AND array, where they can be logically combined using product terms. The outputs of the AND array are then fed to the OR array, where these product terms can be further combined to generate the final output signals. This architecture allows for the implementation of arbitrary Boolean logic functions.

FPLAs are a type of programmable logic device (PLD), often considered a precursor to more advanced devices like Field-Programmable Gate Arrays (FPGAs). While FPLAs are less complex and offer fewer resources than FPGAs, their simpler architecture makes them suitable for tasks requiring smaller amounts of logic. They are typically programmed using a special programmer device and a description file, often written in a hardware description language (HDL) like Verilog or VHDL. Once programmed, the FPLA behaves as if it were a custom-designed logic circuit.