CRYSTAL CLEAR TECHNOLOGY SDN. BHD.
Spec. No: C216x04xxW00 REV. 1.0
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14. Precaution for using LCM
1. Liquid Crystal Display (LCD)
LCD is made up of glass, organic sealant, organic fluid and
polymer based polarizers. The following precautions should be
taken when handling.
a) Keep the temperature within the range of use and
storage. Excessive temperature and humidity could
cause polarization degredation, polarizer peel off or
bubble.
b) Do not contact the exposed polarizer with anything
harder than HB pencil lead. To clean dust off the
display surface, wipe gently with cotton, chamois or
other soft material soaked in petroleum benzin.
c) Wipe off saliva or water drops immediately. Contact
with water over a long period of time may cause
polarizer deformation or colour fading, while an
active LCD with water condensation on its surface
will cause corrosion of ITO electrodes.
d) Glass can be easily chipped or cracked from rough
handling, especially at corners and edges.
e) Do not drive LCD with DC voltage.
2. Liquid Crystal Display Modules.
2.1 Mechanical Considerations
LCM are assembled and adjusted with a high degree
of precision. Avoid excessive shocks and do not
make any alterations or modification. The following
should be noted.
a) Do not tamper in any way with the tabs on
the metal frame.
b) Do not modify the PCB by drilling extra
holes, changing its outline, moving its
component or modifying its pattern.
c) Do not touch the elastomer connector,
especially insert a backlight panel (for
example, EL)
d) When mounting a LCM make sure that the
PCB is not under any stress such as
bending or twisting. Elastomer contacts are
very delicate and missing pixels could
result from slight dislocation of any of the
elements.
e) Avoid pressing on the metal bezel,
otherwise the elastomer connector
could be deformed and lose contact,
resulting in missing pixels.
2.2 Static Electricity
LCM contains CMOS LSI’s and the same
precaution for such devices should apply, namely
a) The operator should be grounded whenever
he/she comes into contact with the module.
Never touch any of the conductive parts
such as the LSI pads, the copper leads on the
PCB and the interface terminals with any
parts of the human body.
b) The modules should be kept in antistatic
bags or other containers to static for storage.
c) Only properly grounded soldering irons
should be used.
d) If an electric screwdriver is used, it should
be well grounded and shielded from
commutator spark.
e) The normal static prevention measures
should be observed for work clothes and
working benches, the latter conductive
(rubber) mat is recommended.
f) Since dry air is inductive to statics, a relative
humidity of 50-60% is recommended.
2.3 Soldering
a) Solder only to the I/O terminals.
b) Use only soldering irons with proper
grounding and no leakage.
c) Soldering temperature: 280 °C
d) Soldering time: 3 to 4 sec
e) Use eutectic solder with resin flux fill.
f) If flux is used, the LCD surface should be
covered to avoid flux spatters. Flux residue
should be removed afterwards.