GLOSSARY

Antifuse   An initially open switch between two points, which may be closed by electrical selection of the location, using a nonreversible process activated by a higher-than-normal voltage. There is a variety of proprietary technologies.

ASIC   Application-specific integrated circuit. This term is used to distinguish integrated circuits for specialized applications, from commodity components.

CAE   Computer-aided engineering. Software tools for use by engineers.

CBIC   Cell-based integrated circuit. An IC mostly composed from a library of proven, pre-designed cells.

CLB   Configurable logic block. Proprietary term describing the internal element used in field-programmable gate array architectures developed by Xilinx, Inc.

CMOS   Complementary metal-oxide semiconductor. The fabrication process used for field-programmable gate arrays.

Commodity component   A widely used type of integrated circuit that is produced in high volume and is readily available from different manufacturers with virtually-identical specifications.

DIL   Dual-in-line integrated circuit package. Common form of packaging with two rows of pins typically spaced by 0.1 inch.

CAL   Configurable Array Logic. Proprietary term describing the architecture employed by Algotronix Ltd.

DRAM   Dynamic random-access memory. A volatile semiconductor memory that requires periodic refresh cycles to maintain its contents.

EPROM   Erasable programmable read-only memory. A nonvolatile semiconductor memory, usually with floating gates, that in normal system operation can be read electrically. It must be removed from the system: for erasure by exposure to ultraviolet light, and for reprogramming. It cannot be erased selectively, that is, every bit must be rewritten even if only one needs to be changed.

EEPROM   Electrically erasable programmable read-only memory. A semiconductor memory that can be erased electrically, otherwise similar to an EPROM.

EPLD   Electrically programmable logic device. A regular assembly of logic components whose functions and connections can be specified electrically and remain nonvolatile.

FPGA   Field-programmable gate array. A regular array of logic components and an interconnection network, both of which can be configured at the point of application.

FPLA   Field-Programmable Logic Array. A Programmable Logic Array structure which can be configured at the point of application.

GAL   Gate array logic. Proprietary term of Lattice Semiconductor Inc.

“Glue” Logic   After choosing the major components, the extra logic that “glues” everything together, that is, that integrates the system into a whole. Often used derogatively to apply to a mass of small- and medium-scale integrated components supporting a few very large-scale integrated components.

HDL   Hardware description language. A formal language for describing digital systems in hardware terms. Examples include VHDL.

LCA   Logic cell array. Proprietary term of Xilinx Inc.

LSI   Large-scale integration. Generally applied to integrated circuits with between 200 and 20,000 transistors.

MOSFET   Metal-oxide semiconductor field-effect transistor. Transistor type used in FPGA circuits.

MSI   Medium-scale integration. Generally applied to integrated circuits with between 20 and 200 transistors.

PAL   Programmable array logic. Proprietary term of American MicroDevices Inc.

PCB   Printed circuit board.

PLA   Programmable logic array. Used to describe specific two-level arrangement with an AND plane feeding an OR plane.

PLD   Programmable logic device. An integrated circuit with a regular pattern of logic elements that can be configured for a particular application.

Simple PLD   LSI component comprising a programmable AND plane followed by a fixed set of logic functions.

Complex PLD   A collection of simple PLDs on a single die with a global interconnection network.

Real Estate   Colloquial term referring to the area taken up by some function or resource of an integrated circuit.

RAM   Random-access memory. Memory with no preferred sequence of addresses.

SRAM   Static random-access memory. Preserves its contents without refresh, provided power supply is maintained.

Switchbox   A general-purpose interconnection network that aids in routing signals from one part of an FPGA to another.

SSI   Small-scale integration. Refers to integrated circuits with fewer than 20 transistors.

Systolic Architecture   A computing structure with many identical processing elements that are composed in an array, and for which the flow of data is highly regular.

VLSI   Very-large-scale integration. Usually restricted to integrated circuits with over 20,000 transistors.