■ PRECAUTIONS
Precautions on the use of Multilayer chip Inductors, Multilayer chip inductors for high frequency, Multilayer chip bead Inductors
4. Soldering
◆Selection of Flux
1. Since flux may have a significant effect on the performance of inductors, it is necessary to verify the following conditions prior to use;
（1）Flux used should be with less than or equal to 0.1 wt%（Chlorine conversion method）of halogenated content. Flux having a strong acidity content should
not be applied.
Precautions
（2）When soldering inductors on the board, the amount of flux applied should be controlled at the optimum level.
（3）When using water-soluble flux, special care should be taken to properly clean the boards.
◆Soldering
1. Temperature, time, amount of solder, etc. are specified in accordance with the following recommended conditions, and please contact us about peak tem-
perature when you use lead-free paste.
◆Selection of Flux
1-1. When too much halogenated substance（Chlorine, etc.）content is used to activate the flux, or highly acidic flux is used, an excessive amount of residue
after soldering may lead to corrosion of the terminal electrodes or degradation of insulation resistance on the surface of the Inductor.
1-2. Flux is used to increase solderability in flow 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.
1-3. Since the residue of water-soluble flux is easily dissolved by water content in the air, the residue on the surface of Inductor in high humidity conditions may
cause a degradation of insulation resistance and therefore affect the reliability of the components. The cleaning methods and the capability of the machines
used should also be considered carefully when selecting water-soluble flux.
◆Soldering
1-1. Preheating when soldering
Heating: Chip inductor components should be preheated to within 100 to 130℃ of the soldering. Cooling: The temperature difference between the
components and cleaning process should not be greater than 100℃.
Chip inductors are susceptible to thermal shock when exposed to rapid or concentrated heating or rapid cooling. Therefore, the soldering process must be
conducted with a great care so as to prevent malfunction of the components due to excessive thermal shock.
Recommended conditions for soldering
［Reflow soldering］
Temperature profile
Temperature（℃）
（Pb free soldering）
300
Peak 260℃ max
10 sec max
200
100
0
Gradually
cooling
Preheating
150℃
60 sec min
Heating above 230℃
40 sec max
※Ceramic chip components should be preheated to
within 100 to 130℃ of the soldering.
※Assured to be reflow soldering for 2 times.
Caution
1. The ideal condition is to have solder mas（s fillet）controlled to 1/2 to 1/3 of the thickness of the inductor, as shown below:
2. Because excessive dwell times can detrimentally affect solderability, soldering duration should be kept as close to recommended times as possible.
Technical
consider-
ations
［Wave soldering］
Temperature profile
Temperature（℃）
（Pb free soldering）
300
Peak 260℃ max
10 sec max
200
100
0
Gradually
cooling
Preheating
150℃
120 sec min
※Ceramic chip components should be preheated to
within 100 to 130℃ of the soldering.
※Assured to be wave soldering for 1 time.
※Except for reflow soldering type.
Caution
1. Make sure the inductors are preheated sufficiently.
2. The temperature difference between the inductor and melted solder should not be greater than 100 to 130℃.
3. Cooling after soldering should be as gradual as possible.
4. Wave soldering must not be applied to the inductors designated as for reflow soldering only.
［Hand soldering］
Temperature profile
Temperature（℃）
（Pb free soldering）
400
350℃ max
3 sec max
300
200
Gradually
cooling
⊿Ｔ
100
0
60 sec min
（※⊿ＴT190℃（3216Type max）, ⊿Ｔ≦ 130℃（3225
Type ming）
※It is recommended to use 20W soldering iron and
the tip is 1φor less.
※The soldering iron should not directly touch the
components.
※Assured to be soldering iron for 1 time.
Note: The above profiles are the maximum allowable
soldering condition, therefore these profiles are
not always recommended.
Caution
1. Use a 20W soldering iron with a maximum tip diameter of 1.0 mm.
2. The soldering iron should not directly touch the inductor.
＊This catalog contains the typical specification only due to the limitation of space. When you consider the purchase of our products, please check our specification.
For details of each product (characteristics graph, reliability information, precautions for use, and so on), see our Web site (http://www.ty-top.com/) or CD catalogs.
mlci0109_reli_e-01
mlci0109_reli-PRP15
TAIYO YUDEN [ TAIYO YUDEN (U.S.A.), INC ]
