Fairchild Semiconductor’s BGA packaged power MOSFETs are not currently available from a second source. However, the company has addressed the second-source issue by developing a dual layout, which allows the BGA packaged MOSFET to be replaced by an SO-8 packaged device. The new layout is described in Fairchild Semiconductor’s Application Note AN-7009 “Dual Layout for BGA and SO8 Packages,” which is available online at www.fairchildsemi.com/an/AN/AN-7009.pdf#page=1 .
In applications such as notebook computers, where SO-8 packaged MOSFETs are popular, the dual pc board layout will enable designers to switch to BGA packaged MOSFETs to obtain the reduced parasitics and improved thermal performance of the BGA package. At the same time, the dual layout gives designers the fall back option of using a standard SO-8 device.