A ꢀ ꢀ ꢁ ꢂ ꢃ Aꢄ ꢂ ꢅ ꢆ S ꢀ E ꢃ ꢂ F ꢂ ꢃ ꢃ A ꢀAꢃ ꢂ ꢄꢅ R S
High Frequency Ceramic Capacitors
ERB Soldering and Mounting
5. Flow Soldering
When sudden heat is applied to the components, the
mechanical strength of the components should go down
because remarkable temperature change causes
deformity inside components. And an excessively long
soldering time or high soldering temperature results in
leaching of the outer electrodes, causing poor adhesion
or a reduction in capacitance value due to loss of contact
between electrodes and end termination.
Standard Conditions for Flow Soldering
Temperature (%)
Soldering
Peak Temperature
Gradual
Cooling
$T
170oC
150oC
130oC
Preheating
In order to prevent mechanical damage in the
components, preheating shoud be required for the both
components and the PCB board. Preheating conditions
are shown inTable 2. It is required to keep temperature
differential between the soldering and the components
surface ($T) as small as possible.
When components are immersed in solvent after
mounting, be sure to maintain the temperature difference
between the component and solvent within the range
shown in Table 2.
Time
5 seconds max.
60-120 seconds
Allowable Soldering Temperature and Time
280
270
260
250
240
Do not apply flow soldering to chips not listed in Table 2.
230
220
Table 2
0
10
20
30
40
Soldering Time (sec.)
Part Number
GRM18/21/31
LLL21/31
Temperature Differential
In case of repeated soldering, the accumulated
soldering time must be within the range shown above.
$T-150%
ERB18/21
ERB18/21
GQM18/21
Recommended Conditions
Pb-Sn Solder
240-250oC
Air
Lead Free Solder
250-260oC
N2
Peak Temperature
Atmosphere
Pb-Sn Solder: Sn-37Pb
Lead Free Solder: Sn-3.0Ag-0.5Cu
Optimum Solder Amount for Flow Soldering
The top of the solder fillet should be lower than the
thickness of components. If the solder amount is
excessively big, the risk of cracking is higher during
board bending or under any other stressful conditions.
Up to Chip Thickness
Adhesive
Continued on the following page.
60 – Innovator in Electronics
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MURATA [ muRata ]
