Refer to the PDF data sheet for device specific package drawings
The ZDN package has been specially engineered with Via Channel technology. This technology allows larger than normal PCB via and trace sizes and reduced PCB signal layers to be used in a PCB design with the 0.65-mm pitch package, and substantially reduces PCB costs. It allows PCB routing in only two signal layers (four layers total) due to the increased layer efficiency of the Via Channel BGA technology.
Via Channel technology implemented on the this package makes it possible to build a product with a 4-layer PCB, but a 4-layer PCB may not meet system performance goals. Therefore, system performance using a 4-layer PCB design must be evaluated during product design.