In this work, the experimental modal analysis (EMA) was performed to establish an equivalent finite element (FE) model for a standard JEDEC drop test printed circuit board (PCB) mounted with packages in a full array. Material properties of the equivalent FE model of the packaged PCB were calibrated through an optimization process with respect to natural frequencies based on EMA results obtained with a free boundary condition. The model was then applied to determine screwing tightness of the packaged PCB corresponding to a fixed boundary condition with the four corners of the PCB constrained, as defined by JEDEC for a board-level drop test.
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