Surfing in the web for Low cost ARM processors i came across a description of a TI OMAP processor used in the Beagle board. To tell in brief the Beagle board is an open source fan-less single board computer which provides the performance of a laptop and is very small in size with 3x3 inch dimensions.
This thing can run a Full pledged Linux, Win CE, Android operating system with HD video capabilities. Reading through the description of the board which mentioned it comes with a ARM cortex A8 processor and 128MB RAM and 256MB NAND flash memory. I found all the peripherals mentioned present on the board but i was wondering where did the RAM and the flash of the system go? because the RAM and the flash memories chips were not found on the board. Thats when i came to know about the PoP method of vertical chip integration used to save board space on the Mother boards.
The Package on Package is an IC packaging method used to stack two or more logic circuits which come in Ball Grid Array(BGA) packages to save space or what we call the PCB real estate area. This method is very useful in Mobile phones which need to be as small as possible to fit in the users hands. The TI OMAP 3530 processor used in the Beagle board comes stacked with a 128 MB LPDDR RAM and 256 MB NAND Flash in the PoP form. This is how it looks like....
It definitely doesnt looks like it is stuffed with a ARM Cortex A8 processor running at 800MHz speed and has 128MB RAM and 256 MB Flash memory in it.
For more details look at the TI official website.