CPU design is the design engineering task of creating a central processing unit (CPU), a component of computer hardware. It is a subfield of electronics engineering and computer engineering.\ CPU design focuses on these areas: datapaths (such as ALUs and pipelines) control unit: logic which controls the datapaths Memory components such as register files, caches Clock circuitry such as clock drivers, PLLs, clock distribution networks Pad transceiver circuitry Logic gate cell library which is used to implement the logic.