5.4.2.3 Maximum Allowable Deflection For LCCs

When a Leadless Chip Carrier (LCC) is vibrated in an axis perpendicular to
its body the solder tends to lift from the filet land. This is a result of PWB
bending stresses. The analysis for the LCC is shown in Equation 5-9 and
calculates the maximum allowable deflection that the solder filets can
withstand before they are stressed beyond the solder materials’ endurance
limits. Once the maximum allowable deflection for the LCC has been calculated,
it will be used in Section
5.4.2.4 along with the expected deflection from Equation 5-3
to determine the maximum allowable PSD input level for this
part.