A mechanics-based strain gage methodology for solder joint reliability assessment

Dynamic Response of PCB Structures to Shock Loading in Reliability Tests

“…Thus, such measurements have become the method of choice in the electronic industry. Strain measurements are conducted by application of strain gages, which are being placed at one or more locations on the board [3,[7][8][9][10][11]. To develop a good understanding of the effect of the board deformations on the strains in and reliability of solder joints, one has to establish meaningful correlations between the strain gage reading(s) and the solder joint loading.…”

“…This was the motivation for JEDEC (Joint Electronic Device Engineering Council) to issue a board-level drop test standard (JEDEC standard JESD22-B111, "Board Level Drop Test Method of Components for Handheld Electronic Products"). In addition to JEDEC tests [8,9] different shock tests are being conducted in the industry [3,7,10,11].…”

“…These tests provide board strain-based design limits that are the basis for the specification documentation for the package subjected to shock tests [4][5][6][7][8]. The tested shock test board assembly consists of a board with one or more packages surface mounted on one side of the board (Fig.…”

Torsional fatigue life prediction method for DRAM module

“…Efforts to suggest a damage parameter by measuring it from user environment and to develop accelerated test method which can simulate user environment are necessary to evaluate reliability of package through life prediction. Mercado et al conducted usecondition-based cyclic bend test [1] and suggested location of strain gage attachment and criterion of strain value that can represent failure [2]. Yamaji et al measured the mechanical user environment of end product, such as key pressing and drop impact by using strain gages [3].…”