Cutting-edge 28 nanometre technology has put the world's biggest contract chip maker ahead of rivals as consumers shift to mobile devices like Apple Inc's iPad and iPhone and away from personal computers.

Analysts predict the company will continue to have robust topline growth over the longer term, although rising inventory levels at end-users like automakers and computer makers have stoked concerns about the current quarter.

Texas Instruments, a key TSMC client, this week forecast surprisingly weak revenue for the fourth quarter, saying its customers were nervous about demand amid a deteriorating global economy.

Net profit for the world's biggest contract chipmaker in the July-September period was T$49.3 billion ($1.68 billion), above the T$45.32 billion average estimate of 22 analysts polled by Thomson Reuters I/B/E/S.

The figure compares with T$41.81 billion in the second quarter and T$30.40 billion for the same quarter a year ago.

TSMC's clients include Texas Instruments and Nvidia.

Before the results announcement, TSMC shares closed down 0.7 percent, in line with a 0.7 percent decline in the broader market.

($1 = 29.2845 Taiwan dollars)

(Reporting by Faith Hung and Clare Jim; Editing by Edwina Gibbs)

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