2-107. A new technique was required to improve reliability and further increase
packaging density. The solution was INTEGRATED CIRCUITS. An IC is a device that
integrates (combines) both active components (transistors, diodes, and so on) and passive
components (resistors, capacitors, and so on) of a complete electronic circuit in a single
chip (a tiny slice or wafer of semiconductor crystal or insulator).
2-108. ICs have almost eliminated the use of individual electronic components (resistors,
capacitors, transistors, and so on) as the building blocks of electronic circuits. Instead, tiny
CHIPS have been developed whose functions are not that of a single part, but of dozens of
transistors, resistors, capacitors, and other electronic elements, all interconnected to
perform the task of a complex circuit. Often these make up a number of complete
conventional circuit stages, such as a multistage amplifier (in one extremely small
component). These chips are frequently mounted on a plastic card called an integrated
circuit board (see Figure 2-24), which plugs into an electronic unit.
Figure 2-24. Typical ICB
2-109. ICs have several advantages over conventionally wired circuits of discrete
components. These advantages include the following:
A drastic reduction in size and weight.
Possible improvement in circuit performance.
However, ICs are made up of parts so closely associated with one another that repair
becomes almost impossible. In case of trouble, the entire circuit is replaced as a single
23 June 2005