If any questions arise whether to use the Rated Ambient Temperature” the Rated Terminal Part Temperature” your usage conditions, please give priority to the Rated Terminal Part Temperature”
“
or “
in
“
.
For more details, please refer to Introduction of the derating curves based on the terminal part temperature” page 14 to 17.
The properly and electrostatically measured taping materials are used for the components, but attention should be paid to the fact that there is some danger the parts absorb on the
top tapes to cause a failure in the mounting and the parts are destructed by static electricity (1kV and more : 1J, 2A, 2B, 2E 0.5kV and more : 1E, Human Body Model 100pF
1.5kΩ) to change the resistance in the conditions of an excessive dryness or after the parts are given vibration for a long time as they are packaged on the tapes. Similarly, care
should be given not to apply the excessive static electricity when mounting on the boards.
●
Ionic impurities such as flux etc. that are attached to these products or those mounted onto a PCB, negatively affect their moisture resistance, corrosion resistance, etc. The flux
＋
−
may contain ionic substances like chlorine, acid, etc. while perspiration and saliva include ionic impurities like sodium (Na ), chlorine (Cl ) etc. Therefore these kinds of ionic
substances may induce electrical corrosion when they invade into the products. Either thorough washing or using RMA solder and flux are necessary since lead free solder contains
ionic substances. Washing process is needed, before putting on moisture proof material in order to prevent electrical corrosion.
●
Please pay attention that the top of an iron does not direct touch to the components. There is a risk that may cause a change in resistance. Take care that another risk may happen
that the protecting coat is carbonized in an instant when touched directly by the top of the iron, also climatic-proof for electric corrosion or insulation of protecting coat may be
dropped down. Be sure not to give high temperature on the top of the iron as it will degrade the protecting coat.
●
Avoid storing components under direct sun rays, high temperature/humidity. Direct sun rays will cause quality change of taping and difficulty of keeping appropriate peeling strength. 5
〜35℃/35〜75%RH, there is no deterioration of solderability for 12 months, but take special care for storing, because condensation, dust, and toxic gas like hydrogen sulfide,
sulfurous acid gas, hydrogen chloride, etc. may drop solderability.
●
The upper electrodes could be peeled off when a heat-resistant masking tape is attached to the mounted chip resistors and then detached from them. It is confirmed that the
adhesiveness gets stronger due to the exposure to heat under mounting. Accordingly, we recommend the use of masking tape be refrained. If the use of heat-resistant masking tape is
unavoidable, please make sure that the adhesives on the tape do not directly come in contact with the product.
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DIY/Open Source Hardware
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