CHAPTER 4
COMPUTER COMPONENTS AND CIRCUITS
INTRODUCTION
The computer’s functions and operations can be very complex. However,
fundamentally they are based upon simple building blocks that are repeated many
times in the computer. The computer uses a binary system: it has two, and only
two, states. The digital functions and operations of the computer are based upon
logic algebra (Boolean algebra), which is a perfect fit for the binary (base 2) number
system. Let’s take these two concepts—logic algebra and binary—and apply them
to the computer’s number systems, logic, circuits, and data types and formats.
To maintain computers effectively, you must understand their components
(number systems, logic, circuits, data types and formats, and power supplies) and
how they make up a computer’s functional areas. You must understand their
functions in a computer and be able to determine if a computer’s components are
functioning properly.
This topic will refresh your knowledge of computer components. Keep in mind
that the technology is ever changing, but the components are common to all
computers; an AND gate works the same in a microcomputer as it does in a large
mainframe. A computer performs arithmetic and logical functions on the input
data, and then outputs data to the appropriate computer or device.
The logic circuits used in a computer will be based on the requirements of the
computer and on what logic circuits best fulfill the requirements. Table 4-1 lists
manuals and documents that provide information on circuits; integrated circuits
(ICs) (linear and digital), their types, identification, methods of production,
packaging, size integration, logic family, and specifications; standard cells
(symbols); circuit types, operations and uses; Boolean algebra; and number
systems. If you want to refresh your knowledge of any of these areas, we
recommend you study the appropriate manuals and/or documents.
After completing this chapter, you should be able to:
Describe how number systems are used in computers
Describe how Boolean algebra can be applied to computers
Describe how ICs are packaged and their various integration sizes
Describe the families of digital logic and differentiate between them
Interpret digital logic gate waveshapes
Describe digital ICs—their groups, logic gates, flip-flops, and functional
uses
4-1
