Samsung DVD-709, Service Manual

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Precautions
1-4 Samsung Electronics
1-3 ESD Precautions
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be dam-
aged easily by static electricity.
Such components commonly are called Electrostati-
cally 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
component 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 dis-
charging wrist strap device, which should be
removed for potential shock reasons prior to apply-
ing power to the unit under test.
(2) After removing an electrical assembly equipped
with ESD devices, place the assembly on a conduc-
tive surface such as aluminum foil, to prevent elec-
trostatic charge buildup or exposure of the assem-
bly.
(3) Use only a grounded-tip soldering iron to solder or
unsolder ESD devices.
(4) Use only an anti-static solder removal devices.
Some solder removal devices not classified as
Òanti-staticÓ can generate electrical charges suffi-
cient 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 your
are ready to install it.(Most replacement ESD
devices are packaged with leads electrically short-
ed together by conductive foam, aluminum foil or
comparable conductive materials).
(7) Immediately before removing the protective ma-
terials from the leads of a replacement ESD device,
touch the protective material to the chassis or cir-
cuit assembly into which the device will be
installed.
CAUTION : Be sure no power is applied to the ch-
assis or circuit, and observe all other safety precau-
tions.
(8) Minimize bodily motions when handling unpack-
aged replacement ESD devices. (Otherwise harm-
less motion such as the brushing together of your
clothes fabric or the lifting of your foot from a car-
peted floor can generate static electricity sufficient
to damage an ESD device).