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comparison to the distance between discrete components mounted on the large chassis. The elements
within the substrate are interconnected on the single substrate itself to perform an electronic function. A
microcircuit does not have any discrete components mounted on it as do printed circuit boards, circuit
card assemblies, and modules composed exclusively of discrete component parts.
Microcircuit Module
Microcircuits may be used in combination with discrete components. An assembly of microcircuits
or a combination of microcircuits and discrete conventional electronic components that performs one or
more distinct functions is a microcircuit module. The module is constructed as an independently
packaged, replaceable unit. Examples of microcircuit modules are printed circuit boards and circuit card
assemblies. Figure 1-35 is a photograph of a typical microcircuit module.
Figure 1-35.—Microcircuit module.
Miniature Electronics
Miniature electronics includes miniature electronic components and packages. Some examples are
printed circuit boards, printed wiring boards, circuit card assemblies, and modules composed exclusively
of discrete electronic parts and components (excluding microelectronic packages) mounted on boards,
assemblies, or modules. MOTHER BOARDS, large printed circuit boards with plug-in modules, are
considered miniature electronics. Cordwood modules also fall into this category. Miniature motors,
synchros, switches, relays, timers, and so forth, are also classified as miniature electronics.
Recall that microelectronic components contain integrated circuits. Miniature electronics contain
discrete elements or parts. You will notice that printed circuit boards and circuit card assemblies are
mentioned in more than one definition. To identify the class (microminiature or miniature) of the unit,
you must first determine the types of components used.
Q37. Standardized terms improve what action between individuals?
Q38. Microcircuit refers to any component containing what types of elements?
Q39. Components made up exclusively of discrete elements are classified as what type of electronics?
SYSTEM PACKAGING
When a new electronics system is developed, several areas of planning require special attention. An
area of great concern is that of ensuring that the system performs properly. The designer must take into
