| 摘要 |
PROBLEM TO BE SOLVED: To prevent void connection of soldering and improve reliability of the connection. SOLUTION: BGA (Ball Grid Array) component 21 comprises a grid of bump solder and are connected to the first and second pad, 33 and 34, of the multilayer wiring board 22 by the solder connection 25. The first pad 33 positioned in the outside 2 row is connected to the surface conductor pattern 29. The second pad 34 positioned inside of the pad 33 is connected to the concave viahole formed nearby through the connection 36 and connected to the inner layer conductor pattern 30. The viahole 35 is disposed at an angle of 45 deg. from the second pad 34 and disposed between the pad 33 and 34. The periphery of the connection 36 and viahole 35 is covered by the solder resist 37. As the surface of the first and second pad, 33 and 34, are flat no air is left and the cream solder is printed. |
