The Taiwan Semiconductor Manufacturing Company has started trial manufacturing of the next generation A6 chips for Apple, according to a Reuters report, citing a source familiar with the matter. This is a sign that the iPad maker is shifting from its traditional chip supplier, Samsung.

The A6 processor is still a distant destination on Apple's chip road map. It isn't expected to appear in products until 2012, and analysts believe it will be quad-core, a first for an Apple A series chip. The A5, used in iPad 2, is a dual-core processor.

The shift has been driven in part by the legal disputes between Apple and Samsung, who has been Apple's sole manufacturer for A4 and A5 processors.

Linley Gwennap, head of the Linley Group, a chip consulting firm, told CNET that he expects Apple to continue to consign production of the A5 processor to Samsung but switch to TSMC for the A6. 

The most significant development would be for Apple to actually contract with TSMC for commercial, high-volume production of the A6. That hasn't been decided yet, according to Reuters. TSMC is the largest contract chip manufacturer in the world and it seems likely that the relationship with Apple would move forward.