Package-on-Package (PoP) is a technique designed to make it possible to vertically combine discrete logic and memory Ball grid array (BGA) packages. Two or more packages are installed on top of one another, i.e. stacked, with a standard interface to route signals between them. This enables the OEMs to create higher density designs, for example in the mobile telephone / PDA market.
Benefits
The most obvious and already mentioned benefit is the board space savings. Another important benefit is the minimized track length between for example a controller and a memory. This results in better electrical performance of the devices, since the shorter routing of interconnections between circuits results in faster signal propagation and reduction in noise and cross-talk.
