Classification of Integrated Circuits

A simple way to classify digital ICs is based on the number of logic gates or components.

Small Scale Integration or SSI contains about a dozen components. Medium Scale Integration or MSI has about 100 logic gates or components. Counters and decoders belong to this category. Large Scale Integration (LSI) deals with thousand components and microcontrollers come in this category. Very Large Scale Integration or VLSI has several thousands of components. Beyond that there is Ultra Large Scale Integration containing million components like the central processing unit or CPU of modern computers.