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Complex Programmable Logic Device

What Does Complex Programmable Logic Device Mean?

A complex programmable logic device (CPLD) is a logic device with completely programmable AND/OR arrays and macrocells. Macrocells are the main building blocks of a CPLD, which contain complex logic operations and logic for implementing disjunctive normal form expressions. AND/OR arrays are completely reprogrammable and responsible for performing various logic functions. Macrocells can also be defined as functional blocks responsible for performing sequential or combinatorial logic.


Techopedia Explains Complex Programmable Logic Device

A complex programmable logic device is an innovative product compared to earlier logic devices like programmable logic arrays (PLAs) and Programmable Array Logic (PAL). The earlier logic devices were not programmable, so the logic was built by combining multiple logic chips together. A CPLD has a complexity between PALs and field-programmable gate arrays (FPGAs). It also has the architectural features of both PALs and FPGAs. The main architectural difference between a CPLD and FPGA is that FPGAs are based on lookup tables, whereas CPLDs are based on sea-of-gates.

The common features of CPLDs and FPGAs are that they both have large numbers of gates and flexible provisions for logic. Whereas common features between CPLDs and PALs include non-volatile configuration memory. CPLDs are leaders in the market of programmable logic devices, having multiple benefits like advanced programming, low cost, being non-volatile and easy to use.


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