A microprocessor (MPU) is a hardware functional unit designed as an integrated circuit( IC). It consists of logical functional units that are controlled by instruction sets and perform arithmetic calculations. A microprocessor contains the arithmetic unit( ALU), control unit( CU), registers and input/output systems as functional units. These functional units are controlled by extensive instruction sets.
The performance criteria of microprocessors
The most important performance criteria of microprocessors include the instruction set, the data word width of the data and address bus and, above all, the computing power with the number of operations per second. Whereby these are determined by the clock frequency and the data word width.
Therefore processors are always designated with the internal data bus width, which indicates the processing data word width: 4-, 8-, 16-, 32- and 64-bit microprocessor
The historical development of microprocessors
While the structure width was 10 µm at the beginning of the development, it decreased to less than 1 µm in the 1990s. During the same period, thanks to the rapid increase in integration density, the number of transistors rose from a few thousand, as in the 4004 in the 1980s, to a few 100,000, as in the 80386, which consisted of 275,000 transistors, and experienced a further increase in the 1990s with SLSI technology to several million transistors in the 1990s and to 100 million up to over 1 billion transistors by 2010.
The rapid development of clock frequency
Parallel to this development, a true performance explosion took place due to the rapidly increasing clock rates and the expansion of bus widths from 4 bits to up to 64 bits. While the first clock rates in the 1970s were still a few hundred kilohertz( kHz), they were several megahertz( MHz) in the 1980s, a hundred and more megahertz in the 1990s and later several gigahertz( GHz).
All these developments were accompanied by new processor architectures with parallel processing such as pipelining, larger caches, richer instruction sets, and the performance symbiosis of two and more processor cores in the form of dual-core processors, quad-core process ors, and other multi-core processors, multiprocessing, and multithreading, which also allowed the performance increase to be implemented.
More recent developments focus on lower supply voltages and the associated reduction in power consumption. Microprocessors are developed for specific applications, but they can also be universally designed, such as the central processing units( CPU) of computers. The areas of application for processors range from computer technology, process automation, consumer electronics and automotive technology, to measurement technology and medical technology, satellite transmission and communications technology, to household technology and building automation. There is hardly an area of life in which processors do not provide functional support.