Daewoo DHC - 2300K, Руководство по обслуживанию

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5
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be
damaged easily by static electricity.
Such components commonly are called
Electrostatically Sensitive Devices(ESD). Examples
of typical ESD devices are integrated circuits and
some field-effect transistors and semiconductor
chip components. The following techniques should
be used to help reduce the incidence of component
damage caused by static electricity.
(1) Immediately before handling any semiconductor
components or semiconductor-equipped
assembly, drain off any electrostatic charge on
your body by touching a known earth ground.
Alternatively, obtain and wear a commercially
available discharging wrist strap device, which
should be removed for potential shock reasons
prior to applying power to the unit under test.
(2) After removing an electrical assembly equipped
with ESD devices, place the assembly on a
conductive surface such as aluminum foil, to
prevent electrostatic charge buildup or exposure
of the assembly.
(3) Use only a grounded-tip soldering iron to solder
or unsolder ESD device.
(4) Use only an anti-static solder removal devices.
Some solder removal devices not classified as
“anti-static” can generate electrical charges
sufficient to damage ESD devices.
(5) Do not use freon-propelled chemicals. These
can generate electrical charges sufficient to
damage ESD devices.
(6) Do not remove a replacement ESD device from
its protective package until immediately before you
are ready to install it. (Most replacement ESD
devices are packaged with leads electrically
shorted together by conductive foam, aluminum
foil or comparable conductive materials).
(7) Immediately before removing the protective
materials from the leads of a replacement ESD
device touch the protective material to the
chassis or circuit assembly into which the
device will be installed.
CAUTION :
Be sure no power is applied to the
chassis or circuit, and observe all other safety
precautions.
(8) Minimize bodily motions when handling
unpackaged replacement ESD devices.
(Otherwise harmless motion such as the
brushing together of your clothes fabric or the
lifting of your foot from a carpeted floor can
generate static electricity sufficient to damage
an ESD device).
1-3 ESD Precautions