Xerox 4400DT - Phaser B/W Laser Printer, Service Manual, Page: 7 / 503

vi Phaser 4400 Laser Printer Service Manual
Electrostatic Discharge (ESD) Precautions
Some semiconductor components, and the respective sub-assemblies that contain
them, are vulnerable to damage by Electrostatic discharge (ESD). These components
include Integrated Circuits (ICs), Large-Scale Integrated circuits (LSIs), field-effect
transistors and other semiconductor chip components. The following techniques will
reduce the occurrence of component damage caused by static electricity.
Caution: Be sure the power is off to the chassis or circuit board, and
observe all other safety precautions.
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Immediately before handling any semiconductor components assemblies,
drain the electrostatic charge from your body. This can be accomplished by
touching an earth ground source or by wearing a wrist strap device
connected to an earth ground source. Wearing a wrist strap will also prevent
accumulation of additional bodily static charges. (Be sure to remove the
wrist strap before applying power to the unit under test to avoid potential
shock.)
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After removing a static sensitive assembly from its anti-static bag, place it
on a grounded conductive surface. If the anti-static bag is conductive, you
may ground the bag and use it as a conductive surface.
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Do not use freon-propelled chemicals. These can generate electrical charges
sufficient to damage some devices.
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Do not remove a replacement component or electrical sub-assembly from its
protective package until you are ready to install it.
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Immediately before removing the protective material from the leads of a
replacement device, touch the protective material to the chassis or circuit
assembly into which the device will be installed.
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Minimize body motions when handling unpackaged replacement devices.
Motion such as your clothes brushing together, or lifting a foot from a
carpeted floor can generate enough static electricity to damage an
electro-statically sensitive device
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Handle ICs and EPROM’s carefully to avoid bending pins.
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Pay attention to the direction of parts when mounting or inserting them on
Printed Circuit Boards (PCB’s).