Electric circuit or module packaged as a single unit with leads extending from it for input, output and power-supply connections. All the electronic devices are formed by selective treatment of a single chip of semiconductor material.

Integrated circuits are categorized according to the number of Transistors or other active circuit devices they contain; an active circuit device is one that receives power from a source other than its input signal.

An ordinary integrated circuit (IC) may contain up to several tens to several hundred; a large-scale integrated circuit (LSI) several hundred to a few thousand; and an extra-large integrated circuit (ELSI), a few thousand or more.