On what basis are integrated circuits (ICs) classified?

Integrated circuits (ICs) are commonly classified according to their level of integration, which historically refers to the number of electronic components, particularly transistors, that can be incorporated into a single chip. Therefore, Option C (Number of Transistors) is the expected answer for this MCQ.

As semiconductor technology developed, manufacturers learned to place increasingly large numbers of transistors and other components onto a single integrated circuit. Based on the level of integration, ICs have traditionally been categorized as SSI (Small-Scale Integration), MSI (Medium-Scale Integration), LSI (Large-Scale Integration), VLSI (Very-Large-Scale Integration), and ULSI (Ultra-Large-Scale Integration).

SSI contains a relatively small number of components, while MSI contains more components. LSI and VLSI represent progressively higher levels of integration. Modern microprocessors and many other advanced chips contain billions of transistors, representing extremely high levels of integration.

The classification is therefore related to the number of components/transistors integrated onto a chip, rather than the manufacturing company or type of computer in which the IC is used.

Key Points:

• IC classification → Level of integration 


• Traditionally measured by the number of transistors/components on the chip.


• SSI → Small-Scale Integration


• MSI → Medium-Scale Integration


• LSI → Large-Scale Integration


• VLSI → Very-Large-Scale Integration

Exam Tip:

More transistors/components on a chip → Higher level of integration ✅