INTEGRATED CIRCUITS

Integrated Circuits, Microprocessors, Chip Sets



Integrated Circuits, Microprocessors, Chip Sets

CPUs basic architecture

The CPU is considered as the brain of computer. The CPU lies on the motherboard, in a form of large integrate circuits, consisting of numerous components and wires. The very basic architecture of any processor involves three major components including Arithmetic Logic Unit (ALU), control unit (CU) and the memory unit (MU). The architecture also deals with the interconnections between these components with the help of sets of wire, known as buses. The memory unit further divides into RAM (Random Access Memory) and registers. Figure 1 shows the basic architecture of 8088 processor (Bucaro S., 2012). The figure represents the over simplified architecture.

Figure 1: Basic CPU architecture

Designing CPU using SSI, MSI, LSI, and VLSI

In the early ages of CPU design, as soon as the transistors and printed circuit boards came into existence, the concept of integrated circuits rose. However, in the beginning, the integrated circuits contained fewer components. As the number of components was few, such integrated circuits lack in functionality. Small Scale Integration was the technology using which early CPU's developed. The SSI based CPUs contained transistors in the order of tens and hence could perform fewer logic operations.

The next generation of CPU design based on the design technology, known as Medium Scale Integration (MSI). This technology enabled more components (in the order of hundreds) to be included on a small circuit board, hence improving the performance and capabilities of the CPU.

Large Scale Integration (LSI) design techniques introduced the concepts of including tens of thousands of transistors on a single chip. These CPUs became part of second generation main memories, and advanced calculators during the period of 1970's.

Very Large Scale Integration (VLSI) is the technology that started in 1980's and continues to the present. Nowadays, the technology enables ...