Integrated Circuits

An integrated circuit (IС) is a collection of interconnected transistors, diodes, resistors, and capacitors mounted in one package or case with as many as fourteen leads.

The word "integrated" does not refer to the mathematical process of adding together an infinite number of infinitesimally small terms, but rather to the fact that all transistors, diodes, and resistors are formed from a single piece of semiconductor material called a "chip" or a "die". If only one chip is present in the case, the IС is called "monolithic"; if several chips are mounted inside the case the IС is called "hybrid". Some integrated circuits contain several thousand transistors and resistors, and so extreme miniaturization is possible.

Because of their extremely small size, integrated circuits tend to be restricted to low power applications. Their small size, however, does enable them to operate at high frequencies. The cost of an IС is considerably less than the total cost of the separate components.

Monolithic ICs are by far the most common, but there are other kinds. Thin-film and thick-film ICs are larger than monolithic ICs but smaller than discrete circuits. With a thin– or thick-film IС, the passive components like resistors and capacitors are integrated simultaneously on a substrate. Then, discrete active components like transistors and diodes are connected to form a complete circuit. Therefore, commercially available thin– and thick-film circuits are combinations of integrated and discrete components¹.

If only a few components have been integrated to form the complete circuit it is an example of small-scale integration (SSI)². As a guide, SSI refers to ICs with less than 12 integrated components.

Medium-scale integration (MSI)³ refers to ICs that have from 12 to 100 integrated components per chip. Large-scale integration (LSI)⁴ refers to more than a hundred components.

The IС is becoming more important as a component to be used in the design of electronic equipment, not only in equipment that must be small and light in weight, but where reliability and performance are demanded. In many areas of application particularly in digital computers, the IС provides more economical designs.

A number of important new developments are being evaluated both in the laboratory and in limited product usage. Some of these promise to bring about significant changes in the way microcircuits are designed and used.

Notes

1.discrete component – дискретный компонент

2.SSI (small-scale integration) – малая интегральная схема

3.MSI (medium-scale integration) – средняя интегральная схема

4.LSI (large-scale integration) – большая интегральная схема

III. Answer the following questions:

1. What is an integrated circuit? 2. What does the word 'integrated' mean? 3. What types of integrated circuits are known to you? 4. What is large scale integration?

IV. Give the main points of text В in 3-5 sentences.

V.Speak about integrated circuits.