Toshiba Corp, Japan's biggest chip maker, eked out a rise in quarterly operating profit on solid demand for its mainstay NAND flash memory chips and kept its earnings outlook unchanged.

The world's No.2 maker of flash memory chips behind Samsung Electronics is becoming increasingly dependent on demand from Apple Inc, as its nuclear power business meets regulatory delays in the wake of the Fukushima nuclear crisis.

Apple's iPad and iPhone and smartphones using Google's Android platform have been bright spots for the chip industry, with Samsung and Toshiba production partner Sandisk hurtling past expectations.

Toshiba, which has been battling weak sales of its PCs and TVs amid a robust yen, retained its annual forecast for an operating profit of 300 billion yen ($4 billion), above the 281 billion yen consensus estimate of 23 analysts polled by ThomsonReuters I/B/E/S.

The industrial electronics conglomerate posted on Monday an operating profit of 76.1 billion yen for July-September, up from 71 billion yen the previous year, although sales fell 3 percent.

Its net profit came to 22.2 billion yen against 27.4 billion yen last year.

Shares in Toshiba, which also competes with Hynix Semiconductor Inc in semiconductors and with GE and Areva in nuclear reactors, have fallen 19 percent this calendar year, broadly in line with Tokyo's electrical machinery subindex.

Its shares closed down 3.9 percent prior to the announcement, underperforming a 1 percent fall in Tokyo's electric machinery subindex. ($1 = 75.760 Japanese Yen)

(Reporting by Mayumi Negishi; Editing by Edwina Gibbs)

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