Panasonic Omnivision PV-9661, Руководство по обслуживанию

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2 PREVENTION OF
ELECTROSTATIC
DISCHARGE (ESD) TO
ELECTROSTATICALLY
SENSITIVE (ES) DEVICES
Some semiconductor (solid state) devices can be damaged
easily by static electricity. Such components commonly are
called Electrostatically Sensitive (ES) Devices. Examples of
typical ES devices are integrated circuits, some field-effect
transistors
and semiconductor "chip" components. The
following techniques should be used to help reduce the
incidence of component damage caused by electrostatic
discharge (ESD).
1. Immediately before handling any semiconductor
component or semiconductor-equipped assembly, drain off
any ESD on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging
ESD wrist strap, which should remove
electrostatic charge for potential shock reasons prior to
applying power to the unit under test.
2. After removing an electrical assembly equipped with ES
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
ES devices.
4. Use only an antistatic solder removal device. Some solder
removal devices not classified as "antistatic (ESD
protected)" can generate electrical charge sufficient to
damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum
foil or comparable conductive material).
7. Immediately before removing the protective material from
the leads of a replacement ES 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 ES 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 (ESD) sufficient to damage an ES device).
"NOTE to CATV system installer:
This reminder is provided to call the CATV system installer's
attention to Article 820-22 of the NEC that provides
guidelines for proper grounding and, in particular, specifies
that the cable ground shall be connected to the grounding
system of the building, as close to the point of cable entry
as practical."
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PV-9661 / PV-9662