MICRO PROCESSOR
The introduction of the microprocessor in the 1970s significantly affected the design and implementation of the CPU’s. Since the introduction of the first microprocessor (the Intel 4004) in 1970 and the first widely used microprocessor (the Intel 8080) in 1974, this class of CPUs has almost completely overtaken all other central processing unit implementation of the time launched proprietary IC development program to up grade their order computer architectures, and eventually produced instruction set compatible microprocessor that backward compatible with their older hardware and software. The term CPU is now applied almost exclusively to microprocessors.
Previous generation of CPUs were implemented as discrete components and numerous small integrated circuits (ICs) on one or more circuit boards. Microprocessor, on the other hand, are CPU manufactured on a very small number o f ICs; usually just one. The overall smaller CPU size as a result if being implemented on a single die means faster switching time because of physical factors like decreased gate parasitic capacitance. This has synchronous micro processor to have clock rates ranging from tens of megahertz to several gigahertz. Additionally, as the ability to construct exceeding small transistor on an IC has increased, the complexity and number of a transistor in a single CPU has increased dramatically.
This widely observed trend is describe by Moore’s law. Which has proven to be fairly accurate predictor of the growth of CPU (and other IC) complexity to date. While the complexity, size, construction, and general form of CPUs have changed drastically over the past sixty years, it is notable that the basic design and the function has not changed much at all. Almost all common CPUs today can be very accurately describe ass von Neumann stored – program machines.
As the aforementioned Moor’s law continue to hold true, concern have arisen about the limits of integrated circuits transistor technology. Extreme miniaturization of electronic gates is causing the effect of phenomena like elector migration and sub threshold leakage to become much more significant. These newer concern are among the many factors causing research to investigate new method of computing such as the quantum computer, as well as to expand the usage of parallelism and other methods that extend usefulness of the classical von Neumann model.