12101C474KAT2A Datasheet, PDF (97/99 Pages) AVX Corporation – AVX Surface Mount Ceramic Capacitor Products

Surface Mounting Guide
MLC Chip Capacitors
POST SOLDER HANDLING
Once SMP components are soldered to the board, any
bending or flexure of the PCB applies stresses to the
soldered joints of the components. For leaded devices, the
stresses are absorbed by the compliancy of the metal leads
and generally don’t result in problems unless the stress is
large enough to fracture the soldered connection.
Ceramic capacitors are more susceptible to such stress
because they don’t have compliant leads and are brittle in
nature. The most frequent failure mode is low DC resistance
or short circuit. The second failure mode is significant loss of
capacitance due to severing of contact between sets of the
internal electrodes.
Cracks caused by mechanical flexure are very easily
identified and generally take one of the following two general
forms:
Mechanical cracks are often hidden underneath the
termination and are difficult to see externally. However, if one
end termination falls off during the removal process from
PCB, this is one indication that the cause of failure was
excessive mechanical stress due to board warping.
Type A:
Angled crack between bottom of device to top of solder joint.
Type B:
Fracture from top of device to bottom of device.
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