Hitachi DVC-605U, Service Manual

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Precautions
1-4
1-3 ESD Precautions
Electrostatically Sensitive Devices (ESD)
Some semiconductor (solid state) devices can be
damaged 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
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 devices.
(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 your
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 ma-
terials 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 ch-
assis 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).