!
Caution
5. Optimum Solder Amount for Flow Soldering
5-1. The top of the solder fillet should be lower than the
thickness of the components. If the solder amount is
excessive, the risk of cracking is higher during board
bending or any other stressful condition.
[Example of Temperature Conditions for Flow Soldering]
[Allowable Flow Soldering Temperature and Time]
In the case of repeated soldering, the accumulated
soldering time must be within the range shown above.
Soldering Time (s)
260
270
280
250
240
230
220
0
10
20
30
40
Soldering Temperature
(°C)
Up to Chip Thickness
Adhesive
Recommended Conditions
Soldering Peak Temperature
Atmosphere
Pb-Sn Solder
240 to 250°C
Air
Lead Free Solder
250 to 260°C
Preheating Peak Temperature
90 to 110°C
100 to 120°C
140 to 160°C (
NFM
)
Air or N
2
30-90 seconds
5 seconds max.
ΔT
Gradual
Cooling
Soldering
Preheating
Preheating
Peak
Temperature
Time
Temperature (°C)
Soldering
Peak
Temperature
Pb-Sn Solder: Sn-37Pb
Lead Free Solder: Sn-3.0Ag-0.5Cu
4-2. Flow Soldering
1. Do not apply flow soldering to chips not listed in table 2.
2. When sudden heat is applied to the components, the
mechanical strength of the components will decrease
because a sudden temperature change causes
deformation inside the components. In order to prevent
mechanical damage to the components, preheating is
required for both of the components and the PCB.
Preheating conditions are shown in table 2. It is required
to keep the temperature differential between the solder
and the components surface (ΔT) as low as possible.
3. Excessively long soldering time or high soldering
temperature can result in leaching of the terminations,
causing poor adhesion or a reduction in capacitance value
due to loss of contact between the inner electrodes and
terminations.
4. When components are immersed in solvent after
mounting, be sure to maintain the temperature
differential (ΔT) between the component and solvent
within the range shown in the table 2.
in section
GR3/GRM
GQM
LLL
GRJ
NFM
18/21/31
18/21
21/31
18/21/31
3D/31/41
ΔT<
=150°C
Series
Chip Dimension
Code (L/W)
Temperature
Differential
Table 2
Continued from the preceding page.
Continued on the following page.
!
Note
• Please read rating and
!
CAUTION (for storage, operating, rating, soldering, mounting and handling) in this catalog to prevent smoking and/or burning, etc.
• This catalog has only typical specifications. Therefore, please approve our product specifications or transact the approval sheet for product specifications before ordering.
