What's Inside Your iPad: Deconstructing the Apple A4 Processor
It's been a wild few days for the iPad: Apple sold 300,000 units of the salsa-making, blendable miracle device on its first day in the world. But for those of us who want a slightly more educational--and somewhat less violent--deconstruction of Apple's latest and greatest gizmo, the folks at iFixit and Chipworks have combined their powers to provide a detailed teardown of the iPad's A4 processor. The two used a variety of methods (scanning electron microscopes, acid baths, x-raying, grinding, and extreme force) to take apart the brains of an iPad and show us what makes it tick.
What did iFixit and Chipworks find inside of the iPad? First off, the A4 processor powering the iPad has three distinct layers: the microprocessor itself and two layers of Samsung RAM. Layering the RAM on top of the processor allows Apple to buy memory from any vendor, not just Samsung.
The above cross-section is of the iPhone's ARM processor and RAM package, showing the processor(center rectangle), as well as RAM dies (two upper rectangles to the right). The three circles are solder beads. Having the RAM close to the processor makes RAM access faster and thus reduces latency. It also makes your battery last longer by cutting power consumption. [Image: iFixit and Chipworks]
How about the GPU? Preliminary software analysis confirms that the iPad is powered by the PowerVR SGX 535 GPU, the same one that drives the iPhone 3GS. As iFixit says, "there's nothing revolutionary here." The iPad's processor is very similar to the one that's in the iPhone, which makes it easier for Apple to cut both power consumption as well as cost when designing and building the iPad. For the rest of the teardown details, as well as some slick images, check out iFixit.
Chip specs aside, is the iPad really just a big iPod Touch with a few more killer apps? Have you done any iPad deconstruction of your own? Let us know how it went in the comments.