An acronym for Programmable Logic Device. While often just called a logic chip, it is an integrated circuit (IC) that can be programmed, with proper equipment, to perform complex functions. A PLD consists of arrays of internal AND and OR gates (see Boolean). A system designer implements a logic design with a device programmer that blows fuses on the PLD to control gate operation. The logic is based on which gates are open and which gates are closed. System designers generally use development software that converts basic code into programmatic instructions a device programmer needs to create a design and put it into operation. PLD types can classified into three groups, PROMs, PALs or GALs and PLAs, and two classifications, Simple PLDs (SPLD) and Complex PLDs, (CPLD).