US Patent 7738259 Shared via decoupling for area arrays components

A solution for mounting decoupling capacitors on a printed wiring board (PWB) used for mounting a high performance ball grid array (BGA) device is described. The via array that connects the BGA device is modified, the modification being that at least a portion of one row of said vias array is missing at least two adjacent vias. The missing vias are replaced by respective shared vias in an adjacent row, and the shared vias are connected to either a power supply or a power return. The shared vias are also provided with via pads on the other side of said PWB, and a decoupling capacitor can be electrically connected across the pair of via pads to decouple the power supply and the power return at the two adjacent vias.