Just what's lurking inside Apple's iPad? We know the company have developed their own SoC, the Apple A4, but so far there's plenty of mystery around what exactly that chipset entails. Over at ArsTechnica they reckon it's a single 1GHz Cortex A8 core and a PowerVR SGX GPU (the latter quietly confirmed last week) based on information from multiple sources. In fact, they go on to suggest, the magic of the Apple A4 SoC is not what it brings to the table, but what it leaves out.
For instance, they reckon the Apple A4 purposefully drops most of the I/O connectivity that a regular Cortex A8-based chipset would include, since Apple know they won't need it. Meanwhile, since the iPad lacks a camera there's probably no SoC imaging/camera blocks, nor all the legacy and multiple-port connectivity blocks you'd usually find on a SoC.
"While it's fun to speculate about what Apple didn't include in the A4, the ultimate point is this: with one 30-pin connector on the bottom and no integrated camera of any kind, the A4 needs a lot less in the way of I/O support than comparable chips that are intended for smartphones or smartbooks. This means that the A4 is just a GPU, a CPU, memory interface block (NAND and DDR), possibly security hardware, system hardware, and a few I/O controllers. It's lean and mean to a degree that isn't possible with an off-the-shelf SoC." ArsTechnica
So, if Apple aren't harnessing their acquired P.A. Semi magic to fettle the iPad's abilities, what might they be using it for? Ars believe the team there is actually working on the chipset for the new, fourth-gen iPhone: the large, bright iPad display - and its power demands - pretty much overwhelms any smaller frugality enhancements in the chipset itself, but that won't be the case for the new smartphone.