JAJSRA3A September 2023 – November 2023 LMG3626
PRODUCTION DATA
Large QFN packages can experience high solder-joint stress. Several best practices are recommended to provide solder-joint stress relief. First, the instructions for the NC1, NC2, and NC3 anchor pins found in Table 4-1 must be followed. Second, all the board solder pads must be non-solder-mask defined (NSMD) as shown in the land pattern example in the Mechanical, Packaging, and Orderable Infromation section. Finally, any board trace connected to an NSMD pad must be less than two thirds the width of the pad on the pad side where it is connected. The trace must maintain this two-thirds width limit for as long as it is not covered by solder mask. After the trace is under solder mask, there are no limits on the trace dimensions. All these recommendations are followed in the Layout Example section.