Integrated Circuits

An integrated circuit (IC) is a small electronic device made out of a semiconductor material. The first integrated circuit was developed in the 1950s by Jack Kilby of Texas Instruments and Robert Noyce of Fairchild Semiconductor.

Integrated circuits are used for a variety of devices, including microprocessors, audio and video equipment, and automobiles. Integrated circuits are often classified by the number of transistors and other electronic components.

Depending upon number of components integrated together, ICs are of following kinds:

• SSI (small-scale integration): Up to 10 logic gates per package.
• MSI (medium-scale integration): From 10 to 200 logic gates per package.
• LSI (large-scale integration): From 200 to 1000 logic gates per package.
• VLSI (very large-scale integration): From 1000 to 10000 logic gates per package.
• ULSI (ultra large-scale integration): More than 10000 logic gates per package.

NOTE: Here keep in mind that the exact size and dimension of package is decided by a consortium. The consortium is often a group of manufacturer companies.

Depending upon the characteristics, ICs are of following kinds:

• TTL (Transistor Transistor Logic): It is a standard and hence used in every IC.
• ECL (Emitter Coupled Logic): ICs based on this logic family work for high speed operation.
• MOS (Metal Oxide Semiconductor): This family works for high component density.
• CMOS (Complimentry Metal Oxide Semiconductor): This family works for low power consumption.