Figure 1-1 shows the structure of TI’s small body nFBGAs. Structure is nearly identical to that of the standard nFBGA shown in the Structure of TI's nFBGA Package image in nFBGA Packaging. The major difference is the package thickness. Standard nFBGAs have a thickness of ~1 mm while the small body variants can range from 0.45 mm - 1 mm. This is achieved by using a thinner substrate material and die attach film instead of epoxy.

Package stack up can be minimized even further by using solder bumps rather than the standard BGA solder balls. The reduced height of the bumps allows the smallest possible package height while offering exceptional board level reliability performance. The package seating height will be dependent upon the solder paste volume and land pad design. Table 1-1 lists all of TIs small body nFBGA packages.

The PCB design guidelines outlined in the Conductor Width/Spacing section of nFBGA Packaging are still applicable to small body nFBGAs. Figure 2-1, Table 2-1 and Table 2-2 outline examples of specific pad, trace, and width dimensions for small body packages.

TI recommends the use of type 3 or finer solder paste when mounting nFBGA. The use of paste offers the following advantages:

• It acts as a flux to aid wetting of the solder ball to the PCB land.
• The adhesive properties of the paste will hold the component in place during reflow.
• Paste contributes to the final volume of solder in the joint, and thus allows this volume to be varied to give an optimum joint.
• Paste selection is normally driven by overall system assembly requirements. In general, the "noclean" compositions are preferred due to the difficulty in cleaning under the mounted components.

TI recommends a pressure safety zone in mounting the nFBGA package. Recommended force should be controlled to 5N maximum for static and 2.5N for impact.

The packaging method depicted in the Recommended Reflow Profile of Eutectic SnPb nFBGA Package image in nFBGA Packaging is the same for small body packages,however, the dimensions need to be reduced according to the package size. Table 3-1 gives examples dimensions for a few of the small body nFBGAs already have in production.

The thermal modeling process outlined in the Solder Ball Collapse image in nFBGA Packaging is applicable to both standard and small body nFBGAs. The results for some of TI’s smaller nFBGA packages are listed in Table 4-1.

There is little difference between the structure of TIs standard and small body nFBGAs. However, small body nFBGA are subjected to rigorous reliability testing to ensure that the minor design differences do not impact reliability, especially BLR. Table 5-1 shows some of the BLR temperature cycle results for some of TI’s small body nFBGA packages