Echelon FT 3150 Smart Transceiver - Manual (Page 142)

Appendix C - Design and Handling Guidelines
136 FT 3120 / FT 3150 Smart Transceiver Data Book
Figure C.7 Typical Manufacturing Work Station
1. The following steps should be observed during board cleaning operation.
a. Vapor degreasers and baskets must be grounded to an earth ground. Operators must likewise be grounded.
b. Brush or spray cleaning should not be used.
c. Assemblies should be placed into the vapor degreaser immediately upon removal from the antistatic container.
d. Cleaned assemblies should be placed in antistatic containers immediately after removal from the cleaning bas-
ket.
e. High-velocity air movement or application of solvents and coatings should be employed only when module
circuits are grounded and a static eliminator is directed at the module.The use of static-detection meters for line
surveillance is highly recommended.
f. The use of static-detection meters for line surveillance is highly recommended.
g. Equipment specifications should alert users to the presence of CMOS devices and require familiarization with
this specification prior to performing any kind of maintenance or replacement of devices or modules.
h. Do not insert or remove CMOS devices from test sockets with power applied. Check all power supplies to be
used for testing devices to be certain there are no voltage transients present.
i. Double-check the equipment setup for proper polarity of voltage before conducting parametric or functional
testing.
j. Do not recycle shipping rails. Continuous use causes deterioration of their antistatic coating.
k. Wrist straps and equipment logs should be maintained and audited on a regular basis. Wrist straps malfunction
and may go unnoticed. Also, equipment gets moved from time to time and grounds may not be reconnected prop-
erly.
Electrostatic Discharge
There are many ways to deal with ESD, including:
• Divert or limit energy from points of contact to circuitry.
• Start with a series of electromagnetic interference (EMI) ferrites or resistors for high frequency filtering.
NOTES:
1. 1/16 inch conductive sheet stock covering bench-top work
area.
2. Ground strap.
3. Wrist strap in contact with skin.
4. Static neutralizer. (Ionized air blower directed at work.) Pri-
marily for use in areas where direct grounding is impractical.
5. Room humidifier. Primarily for use in areas where the relative
humidity is less than 45%. Caution: building heating and
cooling systems usually dry the air causing the relative hu-
midity inside a building to be less than outside humidity.
R = 1 M Ω
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