Chip giant Taiwan Semiconductor Manufacturing Co. has begun shipping the computing brains used in smartphones and tablets to Apple Inc., highlighting the U.S. company's continued push to diversify its suppliers.

TSMC began shipping its first batch of microprocessors to the Cupertino, Calif., company in the second quarter, people familiar with the matter said, supplanting Samsung Electronics Co., which had a lock on the orders for the chips until last year.

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