Repair and maintenance, 1 handling precautions, 2 maintenance philosophy – INFICON MDC-370 Thin Film Deposition Controller User Manual

Page 163

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MDC-370 DEPOSITION CONTROLLER

12. REPAIR AND MAINTENANCE

12.1 HANDLING PRECAUTIONS

Integrated Circuits (I.C.’s) can be damaged by static discharge into their inputs.
This static discharge is the same phenomenon that produces the unpleasant shock
when one grabs a doorknob after walking across a carpet. The likelihood of static
buildup is proportional to the dryness of the air and can be particularly
troublesome in cold, dry climates, or hot desert climates.

In order to minimize the chance of discharging body charge into the I.C. inputs,
always handle circuit boards by the edge, avoiding contact with the connector
area. When moving a board from one surface or work area to another surface or
work area, always personally touch the new surface or location before laying
down or inserting the board so that you, the board, and the surface, or equipment,
are all at the same potential. It is wise in dry climates to minimize the amount of
movement when handling or replacing I.C.’s in circuit boards. When handing a
circuit board or I.C. to another person, always touch the person first.

Wood or paper surfaces are the most forgiving surfaces to work on. Plastic
should be avoided. Metal is O.K. as long as the metal is always touched with the
hand prior to laying down the I.C.’s or circuit boards.

P.C. boards or I.C.’s should never be placed in plastic bags unless they are of the
conductive plastic type intended for this use. These bags are typically black or
pink and are normally labeled as conductive or anti-static. If no conductive
plastic bags are available, boards or I.C.’s can be wrapped in paper, and then
placed in plastic bags or shipping bags.

If the above precautions are observed, the chance of damage will be minimal and
no problems should be encountered.

12.2 MAINTENANCE PHILOSOPHY

The MDC-370 was designed around a maintenance philosophy of board
replacement. Field repair at the component level is not recommended and indeed
can void the warranty. The following sections are intended primarily as an aid in
understanding the operation of the MDC-370 and to help in isolating problems to
the board level.

All electronic components, with the exception of the power supply transformer,
are mounted on plug-in assemblies for ease of removal and replacement. The
circuitry is partitioned among plug-in modules on a functional basis to make fault
isolation to the plug-in assembly level as straightforward as possible.

Most problems can be diagnosed to the board level without external test
equipment and verified by simple board replacement.

REPAIR AND MAINTENANCE

12-1

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