components consist of wave generators and wave
shapers. In computers, waveforms must be turned on
and off for specific lengths of time.
COMPUTER DATA TYPES AND FOR-
MATS —The smallest data element is the bit. Next
comes the nibble, which is four bits. The byte is 8 bits.
The word lengths vary depending on the computer and
are the same length as the registers used in the computer,
usually 16, 30, 32, or 64 bits. The double word is twice
the length of the word.
POWER SUPPLIES —All digital computers have
an internal power supply. The power supply in the
computer does not supply power. It receives ac voltage
from a source and converts it into useable dc voltage(s).
Most computers require multiple dc voltages and levels.
The dc is then distributed to where it is needed. The
power supply in a computer is a switching power
supply. This means the power supply can handle quite
a range of power supply irregularities with minimal
difficulties. Power supplies have four basic sections.
They can handle a range of input voltages and
frequencies.
COMPUTER POWER SUPPLY PROTEC-
TION —The computer’s power supply must protect the
computer from the incoming power, the distributed
power, and/or temperature inside the computer’s
cabinet and/or modules. When overtemperature,
overvoltage, or overcurrent conditions occur, the power
supply will generally shut off.
EXTERNAL COMPUTER PROTECTION
DEVICES —External computer protection devices
include protection devices and backup power.
Learn all you can about the internal operation of
computers and their circuits. You will need this
information to test computer circuits—digital and
linear, to identify faulty components and circuits, and
to remove and replace (or repair) faulty components and
circuits.
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