08051A101BA2A datasheet(97/99 Pages) AVX

97 / 99 page

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.

08051A101BA2A Datasheet(PDF) 97 Page - AVX Corporation