Precautions
1-3 ESD Precautions
Electrostatically Sensitive Devices (ESD)(7) Immediately before removing the protective ma-
terials from the leads of a replacement ESD
Some semiconductor (solid state) devices can bedevice, touch the protective material to the chassis
damaged easily by static electricity.or circuit assembly into which the device will be
Such components commonly are called Electrostati-installed.
cally Sensitive Devices(ESD). Examples of typical
ESD devices are integrated circuits and some field-CAUTION : Be sure no power is applied to the ch-
effect transistors and semiconductor chipassis or circuit, and observe all other safety
components. The following techniques should be usedprecautions.
to help reduce the incidence of component damage
caused by static electricity.(8) Minimize bodily motions when handling
unpackaged replacement ESD devices. (Otherwise
(1) Immediately before handling any semiconductorharmless motion such as the brushing together of
component or semiconductor-equipped assembly,your clothes fabric or the lifting of your foot from a
drain off any electrostatic charge on your body bycarpeted floor can generate static electricity
touching a known earth ground. Alternatively,sufficient to damage an ESD device).
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).
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ACEC
