How Does a Microprocessor Work?

Features

Microprocessors have become the movers and shakers of our everyday world. We use them in computers, televisions, watches, microwaves and practically every other electronic device. Their micro-size is no reflection of the myriad capabilities these chips possess, ranging from 2 to 3 mm square to maybe an inch thick. Silicon makes up the material of a microprocessor chip. Sliced wafer thin, silicon serves as an ideal conductor and insulator for transmitting electrical currents throughout the components of the chip. The finished product is an integrated circuit composed of layers of built-in wiring and transistors. Through the use of laser light, circuit outlines are etched onto a silicon surface through a mask or stencil design. A simple chip can have as many as 3,000 transistors, with as narrow a spacing of 60 nanometers between each one.

Function

A microprocessor is the central processing unit in a computer. It receives, transmits and coordinates every command and process carried out by the system. Electrical currents, moving through wires and transistors, are converted into usable messages through the use of a Boolean logic language. Based on the "on/off" frequency of current moving through transistor circuits, this Boolean logic communicates system commands to and from receiving devices within the computer. The microprocessor communicates within two primary capacities: logic and the processing of information. These processes are handled by two components within the chip:
*Arithmetic logic unit (ALU), responsible for all commands requiring an arithmetic or logic function
* Control unit (CU), which handles the information processing from the computer's memory

From these units within the chip, clusters of wires called "bus" lines send and receive information to and from system devices.

Potential

The first microprocessor chip was designed in 1974. Since that time, technological advancements continue to reduce the size requirements of chips while doubling their processing capability. This continued progress has made for a more efficient unit, and material costs have gone down considerably.

The next step toward further development lies within the field of nanotechnology. This field works within the molecular/subatomic realm of science. Its purpose is to rebuild the most basic of materials--atoms and molecules--from the ground up. Currently, nanotechnologists are working to replicate the microprocessor chip model on a molecular scale. Once completed, information-processing capabilities will dwarf our current processing abilities. These improvements are expected to radically alter technology as we know it today.

Resources

• One Smart Click: Microcontroller and microprocessor resources
• Nanowerk: Nanotechnology computing