Issue link: https://iconnect007.uberflip.com/i/550232
August 2015 • SMT Magazine 45 Case 1 Package description: • FBGA • 144I/O • 11 x 18.5 mm • 0.8 x 1.0 mm pitch • SnPb • 0.55 mm ball diameter Table 1 shows the results of units that were sent to a lab for analysis. According to the only standard at the time (JEITA), this parts maximum warpage of 0.15 mm (5.9 mil) is well within spec- ification. However, a number of users reported the package as being prone to HoP defects when assembling this part with typical SMT process. The component warpage is concave at re- flow, and as a result most HoP was found in the corner joints. The graph in Figure 9 shows the actual measurements of the part at its maxi- mum warpage. (Please note that the part was measured upside-down with the solder balls removed. Therefore to aid with visualization the graph was rotated 180 degrees to show the component warpage as it would be on the board during the SMT reflow process.) Table 1: results of the warpage measurement of two bga from case 1. figure 9: 2D plot of the warpage measurement of the BgA from case 1 (Shown upside-down for clarity). WARPAGE ACCEPTANCE PROPOSAL continues FeAture