iPad equipped to deliver richer graphics
The 64bit path between the A4 processor and main memory provides twice the memory bandwidth as in the iPhone and iTouch (Click on image to view teardown).
UBM TechInsights' teardown of the Apple iPad found it has an unusually high processor-to-memory channel, an abundance of touchscreen silicon and a novel case design. The report shows Samsung and Broadcom are among the major silicon suppliers in the system.
Apple's A4 processor is the most significant chip in the iPad, and holds the biggest surprise found in the teardown. The chip sports a 64bit path to main memory, twice the width of the memory buses used on Apple iPhone and iPod Touch devices, "indicative of the need for richer graphics" in the iPad, said David Carey, VP of technical intelligence at UBM TechInsights and author of the report.
Samsung also supplied NAND flash used in the 64Gbyte iPad Carey examined. Toshiba supplied flash in other models.
The iPad uses three touchscreen chips instead of one typically found in an iPhone or iPod Touch. Both Broadcom controllers used in past Apple systems—the BCM5974 and BCM5973—make an appearance here, along with a Texas Instruments analog chip.
The number of touchscreen chips is "not all that surprising given the size and resolution of the display," said Carey.
A Broadcom BCM4329 combo Wi-Fi/Bluetooth chip may also be used in the iPad, according to speculation from one on-line teardown site after seeing pictures released by the Federal Communications Commission.
Carey praised the unique stair-step pattern molded into the aluminum back panel of the iPad. It provides greater ruggedness for the case as well as a way to secure multiple subassemblies used inside the design.
Among other iPad design wins, Cirrus Logic had an audio codec, Carey said Linear Technology had two charger ICs and he speculated Dialog Semi had a power management chip.
The Apple iPad as torn down by David Carey of UBM TechInsights (Click on image to enlarge).
Based on pictures from the FCC, the 3G cellular data board for the iPad "looks similar to what's in 3GS iPhone right now," Carey added.
Indeed, many of the chips appeared in versions of the iPhone and iPod. "They have done reuse wherever possible," said Carey.
The iPad Carey examined used a 1024x768 pixel LCD he speculated was made by Sanyo-Epson Imaging, now part of Sony. LG Electronics also provides displays for the iPad.
One non-technical conclusion Carey shared after tearing down the tablet: "I want one."
According to market watcher iSuppli, Apple could sell as many as 7.1 million iPads this year, though International Data Corp. estimated 2010 tablet sales at six million for the entire industry.
- Rick Merritt
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