ALU (Arithmetic Logic Unit)

Concept Definition

An ALU is an elementary building block of computing architectures that performs both arithmetic (Ex.: sum, difference, increment,…) and logic (Ex.: AND, XOR, inversion,…) operations on binary bits ('0' and '1'). In classical microelectronics, ALU can be designed to perform complex functions, yet the resulting higher circuit complexity and power consumption are detrimental. Instead, simpler ALU are cascaded into CPU or GPU circuits with a finite propagation delay between inputs and outputs that imposes a finite bandwidth and still a significant circuit complexity.