When we picked up our iPad 4 on Nov. 2 (coincidentally, at the same time we picked up our iPad mini), we took it to our lab as soon as we could to take it apart and analyze what, if any, differences there were between this new iPad and the iPad 3.
Almost instantly upon taking the iPad 4 apart, we at UBM TechInsights discovered a product that was not much different at all from the iPad 3. In fact, apart from the change in processors (from the Apple A5X to the Apple A6X) and a move to Apple's proprietary Lightning connector dock, there isn't anything new in terms of the semiconductors that make up the tablet. One has to wonder if Apple expects to sell the same type of volume (usually tens of millions) of this new iPad if the general perception is this that it's just the iPad 3 with a faster processor.
Consequently, the major design winners from the Apple iPad 3 retain their sockets in the iPad 4, including longtime partner Broadcom, which retained three major design wins from the iPad 3. Two of these wins for were for touchscreen controllers (the BCM5974 and the BCM5973 both of which have been found in the previous iPads and the first generation of the iPhone). Broadcom's other major design win is the company's four-in-one combo wireless chip, the BCM4334, which was also found in the iPhone 5 and Samsung Galaxy S3. Below are some images of the Broadcom ICs we've analyzed using our de-encapsulation (decap) process:
Inside the Murata module containing the Broadcom BCM4334
Die photo of the BCM5973A (click on image to enlarge).