Esd Precautions - Samsung MM-77 Service Manual

2-3. ESD, Precautions
Electrostatically SensitiveDevices (ESD)
Some semiconductor (solid state) devices can be
damaged easily by static electricity.
Such components commonly are called Electro-
statically Sensitive Devices (ESD). Examples of typical
ESD devices are integrated circuits and some field-
effect transistors and semiconductor chip com-
ponents. 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 aharge 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 con-
ductive 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 device.
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 damge
ESD devices.
MM-77
(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
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.
@
Minimize bodily motions when handling unpack-
aged 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).