Citizen CBM-202PC-04, Руководство пользователя

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CBM-202PC-04 User’s Manual
41 CITIZEN
Fig. 9.3 Vapor Phase Reflow Recommended Conditions
6.4 Cleaning Method
After soldering, eliminate/clean remaining flux off the PCB because it affects reliability of the
parts and PCB wiring, as a rule.
As an example, ultrasonic cleaning is employed under the following conditions. In order to
prevent destruction of the device, pay attention to an applied frequency, electric
power(particularly peak power), time and resonance of the device.
• Frequency
----- 28~29kHz (The device should not resonate)
• Ultrasonic output ----- 15W/each time
• Time
----- 30sec or less
• Others ----- The device and PCB should not directly touch a vibration source.
6.5 Storage Method
The epoxy resin used for the plastic package cannot resist absorbing moisture when it is stored
in a high-humidity place. If more moisture is absorbed, it will be abruptly vaporized at the
time of soldering and cause exfoliation of the resin/lead frame interface, resulting in the cracks
of the package in the worst case. As it is important to store in a dry atmosphere(preferably
normal temperature and humidity; 5~35ºC and 45~75 % RH as guides), the package is packed
damp-proof. After unpacking it, store it under a prescribed environment in order to minimize
moisture absorption, and perform reflow mounting as quickly as possible. When you re-store
it in damp-proof packing, put moisture-free silica gel in it and seal again. When you want to
eliminate moisture absorbed during transportation, storage, or handling, it is recommended to
dry(At 125ºC) for 16~24 hours.
The external terminals should be stored unprocessed. This is to avoid a soldering failure due
to occurrence of rust at the time of mounting.