PRECAUTIONS
CAPACITORS
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4. Soldering ◆Selection of Flux
1. When soldering capacitors on the board, flux should be ap-
plied thinly and evenly.
2. Flux used should be with less than or equal to 0.1 wt%
(equivalent to Chroline) of halogenated content. Flux hav-
ing a strong acidity content should not be applied.
3. When using water-soluble flux, special care should be taken
to properly clean the boards.
◆Wave Soldering
1.Temperature, time, amount of solder, etc. are specified in
accordance with the following recommended conditions.
2. Do not immerse the entire capacitor in the flux during the
soldering operation. Only solder the lead wires on the bot-
tom of the board.
◆Recommended conditions for using a soldering iron:
Put the soldering iron on the land-pattern.
Soldering iron's temperature - below 350℃
Duration - 3 seconds or less
Numbers of times - 1 times
The soldering iron should not directly touch the capacitor.
1. Flux is used to increase solderability in wave soldering, but if too much is applied, a large
amount of flux gas may be emitted and may detrimentally affect solderability. To minimize
the amount of flux applied, it is recommended to use a flux-bubbling system.
2. With too much halogenated substance (Chlorine, etc.) content is used to activate the flux,
an excessive amount of residue after soldering may lead to corrosion of the terminal elec-
trodes or degradation of insulation resistance on the surface of the capacitors.
3. Since the residue of water-soluble flux is easily dissolved by water content in the air, the
residue on the surface of capacitors in high humidity conditions may cause a degradation
of insulation resistance and therefore affect the reliability of the components. The clean-
ing methods and the capability of the machines used should also be considered carefully
when selecting water-soluble flux.
1. If capacitors are used beyond the range of the recommended conditions, heat stresses
may cause cracks inside the capacitors, and consequently degrade the reliability of the
capacitors.
2. When the capacitors are dipped in solder, some soldered parts of the capacitor may melt
due to solder heat and cause short-circuits or cracking of the ceramic material. Deteriora-
tion of the resin coating may lower insulation resistance and cause a reduction of with-
stand voltage.
1. If products are used beyond the range of the recommended conditions,heat stress may
deform the products,and consequently degrade the reliability of the products.
5. Cleaning ◆Board cleaning
1. When cleaning the mounted PC boards, make sure that cleaning
conditions are consistent with prescribed usage conditions.
1. The resin material used for the outer coating of capacitors is occasionally a wax sub-
stance for moisture resistance which can easily be dissolved by some solutions. So
before cleaning, special care should be taken to test the components vulnerability
to the solutions used.
When using water-soluble flux please clean the PCB with purified water sufficiently
and dry thoroughly at the end of the process. Insufficient washing or drying could
lower the reliability of the capacitors.
6. Post-cleaning-process ◆Application of resin molding, etc. to the PCB and components.
1. Please contact your local Taiyo Yuden sales office before
performing resin coating or molding on mounted capacitors.
Please verify on the actual application that the coating process
will not adversely affect the component quality.
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1-1. The thermal expansion and coefficient of contraction of the molded resin are not neces-
sarily matched with those of the capacitor. The capacitors may be exposed to stresses
due to thermal expansion and contraction during and after hardening. This may lower the
specified characteristics and insulation resistance or cause reduced withstand voltage by
cracking the ceramic or separating the coated resin from the ceramics.
1-2. With some types of mold resins, the resin's decomposition gas or reaction gas may
remain inside the resin during the hardening period or while left under normal conditions,
causing a deterioration of the capacitor's performance.
1-3. Some mold resins may have poor moisture proofing properties. Please verify the con-
tents of the resins before they are applied.
1-4. Please contact Taiyo Yuden before using if the hardening process temperature of the
mold resins is higher than the operating temperature of the capacitors.
Technical considerationsStages Precautions
Precautions on the use of Axiel Leaded Ceramic Capacitors
◆Mechanical considerations
1. Be careful not to subject the capacitors to excessive me-
chanical shocks. Withstanding voltage failure may result.
2. If ceramic capacitors are dropped onto the floor or a hard
surface they should not be used.
1. Because the capacitor is made of ceramic, mechanical shocks applied to the board
may damage or crack the capacitors.
2.Ceramic capacitors which are dropped onto the floor or a hard surface may develop
defects and have a higher risk of failure over time.
7. Handling
1. Under high temperature/high humidity conditions, the decrease in solderability due to
the oxidation of terminal electrodes and deterioration of taping and packaging char-
acteristics may be accelerated.
◆Storage
1. To maintain the solderability of terminal electrodes and to keep
the packaging material in good condition, care must be taken to
control temperature and humidity in the storage area. Humidity
should especially be kept as low as possible. Recommended
conditions: Ambient temperature Below 40 ℃ Humidity Below
70% RH. Products should be used within 6 months after deliv-
ery. After the above period, the solderability should be checked
before using the capacitors.
2. Capacitors should not be kept in an environment filled with de-
composition gases such as (sulfurous hydrogen, sulfurous acid,
chlorine, ammonia, etc.)
3. Capacitors should not be kept in a location where they may be
exposed to moisture, condensation or direct sunlight.
8. Storage conditions