Programmable logic device definition of Programmable logic device in the Free Online Encyclopedia.

PLD

(Programmable Logic Device) Refers to a variety of logic chips that are programmable at the customer's site, the customer being the vendor of the finished chip, not the end user. Programmability of logic means that new chip designs can be tested and easily changed without incurring the huge photomask costs for chips completed in a semiconductor fab. In addition, memory-based PLDs can be reprogrammed over and over, which allows working products to be upgraded at the user's site.

PLDs are prefabricated with different types of logic circuits (from a handful to hundreds of thousands), all waiting to be interconnected according to the customer's requirements. See ASIC, soft core and adaptive computing.

Programmable Once (Fusible Links and Antifuse)
Fuse-based PLDs are permanent "one-time programmable" (OTP) chips. "Fusible links" are programmed by electrically melting conductive aluminum traces (blowing microscopic fuses). "Antifuse" is the opposite. Instead of destroying conducting links, they are "grown" by sending charges into tiny blocks of insulating silicon that become conductive silicon.

Reprogrammable (Memory Based)
Reprogrammable PLDs store their logic design in an EPROM, EEPROM, flash or SRAM memory that associates each programmable connection point with a memory cell (is the connection open or closed). SRAM-based PLDs are reloaded at startup, making them dynamic and adaptive to new requirements on the spur of the moment.

SPLDs and CPLDs
Simple PLDs (SPLDs) are devices with an AND array feeding an OR array or something similar, the differences being whether one or both arrays are programmable. SPLDs are programmed via fusible link, antifuse, EPROM, EEPROM or flash. Complex PLDs (CPLDs) are formed from a number of SPLDs connected together by a programmable switching matrix. CPLDs are typically EEPROM, flash and SRAM based.

PLDs are always used for logical functions, and programmable storage chips such as PROMs and EPROMs are considered PLDs if they contain program code rather than just data.

FPGAs
Field programmable gate arrays are another major programmable logic technology that some vendors classify under the PLD umbrella while others keep them separate. In either case, both FPGAs and PLDs fall within the "field programmable device" (FPD) category (see FPGA).

The ASIC Family

PLDs fall under the most generic definition of application specific ICs (ASICs). (Diagram courtesy of Clive Maxfield, www.techbites.com)

PLD - Programmable Logic Device

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No references found	Divided into two general categories: Field Programmable Gate Arrays (FPGA) and Complex Programmable Logic Devices (CPLD). Fujitsu and Lattice Strengthen Partnership; Companies Sign ... by JCN Newswires Altera Corp, the San Jose, California-based provider of programmable logic devices and associated software tools, has reported third-quarter net income up 38. Altera Posts Strong Q3 on New Product Sales by Computergram International AMD produces processors, flash memories, programmable logic devices, and products for communications and networking applications. AMD AND GATEWAY COLLABORATE ON PC AND SYSTEM PRODUCTS by PC Business Products	program tape Program Temporary Fix program test program testing time program time program trading program transformation program, computer program-sensitive fault program-to-program communications programmability programmable Programmable Airline Reservation System Programmable Array Logic programmable calculator programmable controller Programmable controllers programmable counter programmable decade resistor programmable device programmable electronic system Programmable Interrupt Controller programmable keypad programmable logic array programmable logic controller Programmable logic device programmable metallization cell programmable power supply programmable read-only memory programmable shading programmatic interface programmatically programme chart programmed check Programmed Control Programmed Data Processor programmed dump programmed function key PROgrammed Graph REwriting Systems programmed halt programmed instruction Programmed Learning programmed logic array Programmed Machining programmed marginal check programmed operators programmed stop Programmed Textbook programmed turn programmer programmer analyst	Programmable Interface Device Programmable Interface Unit Programmable Interrupt Controller Programmable Interrupt Controller Programmable Interrupt Controller Programmable Interrupt Device Programmable Interrupt Timer Programmable Interval Timer Programmable ISDN Audio Front End Programmable Josephson Voltage Standard Programmable Kernel Execution Unit Programmable Key Storage Device programmable keyboard programmable keypad Programmable Lab on A Chip Programmable Limit Switch Programmable logic Programmable logic array Programmable logic array Programmable logic array Programmable Logic Block Programmable Logic Cell Array Programmable Logic Circuit Programmable logic control Programmable logic control Programmable logic controller Programmable logic controller Programmable logic controller Programmable logic controllers Programmable Logic Design Programmable logic device Programmable Logic Element Programmable Logic Relay Programmable Logic Sequencer Programmable Logic Unit Programmable Low Pass Filter Programmable Low Voltage Detection Programmable Machine Controller Programmable Magnetic Tape System Programmable Memory Management Unit Programmable Metallization Cell Programmable Metallization Cell Programmable Micro-Logic Programmable Modular Communications System Programmable Multi-Level Interrupt Controller Programmable Multizone Furnace Programmable Object-centered EnvironMent Programmable Object/Option Select Programmable Optical Add/Drop Multiplexer Programmable Optical Analogic Array Computer Programmable Option Devices Programmable Ordnance Technology programmable pacemaker Programmable Parallel Interface Programmable Peripheral Interface Programmable Phase-Locked Loop

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Divided into two general categories: Field Programmable Gate Arrays (FPGA) and Complex Programmable Logic Devices (CPLD).

Fujitsu and Lattice Strengthen Partnership; Companies Sign ... by JCN Newswires

Altera Corp, the San Jose, California-based provider of programmable logic devices and associated software tools, has reported third-quarter net income up 38.

Altera Posts Strong Q3 on New Product Sales by Computergram International

AMD produces processors, flash memories, programmable logic devices, and products for communications and networking applications.

AMD AND GATEWAY COLLABORATE ON PC AND SYSTEM PRODUCTS by PC Business Products

program tape

Program Temporary Fix

program transformation

program, computer

program-sensitive fault