Linley on Mobile
Apple A6 Delayed for TSMC 28nmAugust 22, 2011
Author: Kevin Krewell
The Taiwan Economic News is reporting that TSMC will produce Apple’s next-generation processor, presumably called the A6, and has recently provided samples of the chip to Apple. The story further reports that the new processor will use TSMC’s 28nm bulk process as well as the foundry’s 3D die-stacking technology. After a mask spin, a final version of the chip will enter production in 2Q12 “at the earliest.”
We believe this timing makes sense given the choice of 28nm technology; this pace would make the A6 one of the first 28nm mobile processors (along with Qualcomm’s MSM8960) to enter production. This schedule, however, breaks Apple’s annual processor-upgrade cycle and will delay any products using the A6 until at least June 2012.
We expect the A6 will be a quad-core ARM Cortex-A9 design, which would be competitive with next year’s best mobile processors. In 2012, Nvidia will offer a quad-core Cortex-A9 processor, and Qualcomm will have the aforementioned MSM8960, a dual-core A15-class processor operating at 1.7GHz. Fabricating Apple’s A6 in 28nm (instead of the 40nm process Nvidia is using for its quad-core part) will reduce both die cost and power, yielding a much better product.
TSMC’s 3D stacking technologies include silicon-interposer and bump-on-trace methods. Apple’s choice of this approach would be a boon to TSMC packaging partner Advanced Semiconductor Engineering (ASE). The earlier A4 and A5 processors use traditional die stacking to combine the processor and a DRAM chip in a single package. The A6 could use 3D stacking to incorporate additional DRAM or flash memory, or to boost interconnect speed.
The A6 delay means that if Apple launches the iPad 3 in January 2012, following its usual schedule, the tablet will have to use the same A5 processor as the current iPad 2, relying on the rumored new high-resolution “Retina” display to drive the upgrade cycle. Apple could then deliver a midyear iPad upgrade, which would be unusual for the company, or it could plug the A6 into next year’s iPhone first and then into the iPad in early 2013.
The foundry switch is not without risk. Apple is betting that TSMC will be able to meet the production needs of another high-volume customer on its brand-new 28nm process and 3D die-stacking technology. In the past, TSMC has had problems with new technology (for example, early 40nm yield problems and the Nvidia “bump-crack” issue) that would be unacceptable to a demanding customer like Apple.