Ricoh LF110, Руководство по обслуживанию

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3
ESD PRECAUTIONS
Certain semiconductor devices can be easily damaged by static electricity. Such
components are commonly called “Electrostatically Sensitive (ES) Devices”, or
ESDs.
Examples of typical ESDs are: integrated circuits, some field effect transistors, and
semiconductor “chip” components.
The techniques outlined below should be followed to reduce the chance that
components will be damaged by static electricity.
!
CAUTION
Be sure no power is applied to the chassis or circuit, and observe all other
safety precautions.
1. Prior to handling any semiconductor component or semiconductor equipped
assembly, remove any electrostatic charge from your body by grounding
yourself. Alternatively, use a commercially available wrist strap device; which
should be removed for safety reasons prior to applying power to the unit.
2. After removing an electrical assembly equipped with ESDs, place the assembly
on a conductive surface, such as aluminum, copper foil, or conductive foam, to
prevent electrostatic charge buildup.
3. Use only a grounded tip soldering iron to solder or de-solder ESDs.
4. Use only an “antistatic” solder removal device. Some solder removal devices
not classified as “antistatic” can generate electrical charges that may damage
ESDs.
5. Do not use Freon propelled chemicals. When sprayed, these can generate
electrical charges that may damage ESDs.
6. Do not remove a replacement ESD from its protective packaging prior to
installing it. Most replacement ESDs come packaged with all leads shorted
together by conductive foam, aluminum foil, or a comparable conductive
material.
7. Immediately before removing the protective shorting material from the leads of
a replacement ESD, touch the protective material to the chassis or circuit
assembly into which the device will be installed.
8. Maintain continuous electrical contact between the ESD and the assembly into
which it will be installed, until the unit is completely plugged or soldered into the
circuit.
9. Minimize unnecessary movement to unpackaged replacement ESDs. Normal
motions, such as the brushing together of clothing fabric or lifting one’s foot
from a carpeted floor, can generate static electricity that may damage an ESD.