* Q3 core profit up 338 mln eur vs poll avg 323 mln
* Q3 revenue 1.831 bln eur vs poll avg 1.826 bln
* Affirms FY guidance (Adds further details on results, automotive revenue)
FRANKFURT, Aug 1 (Reuters) - German chipmaker Infineon , the top supplier of power controls to auto and industrial markets, on Tuesday posted revenue in line with forecasts while profit topped expectations in spite of a recent currency-affected drop in autos revenue.
Third-quarter operating income, excluding certain items, rose 33 percent to 338 million euros ($399.7 million), compared with analyst forecasts, on average, for an increase of 27 percent to 323 million euros, according to a Reuters poll.
Revenue for the fiscal quarter ended in June rose 12.2 percent to 1.831 billion euros, Infineon said. The consensus forecast was 1.826 billion euros, an increase of 11.9 percent, according to 13 analysts polled by Reuters.
Automotive revenue, which represented 42 percent of Infineon sales, declined by 2 percent in the June quarter compared to the fiscal second quarter ended in March, but was nonetheless up 13 percent year-on-year. Its three other segments - industrial power, power management and security - all showed revenue gains.
The decline in its automotive components business mainly reflected the effect of translating U.S. dollar revenue into euros for reporting purposes amid a weakening dollar, it said. Otherwise the business was stable, while demand for driver assistance systems was slightly higher than earlier this year.
The company reaffirmed its outlook for annual revenue growth of 8 to 11 percent for its fiscal 2017 year ending in September, and said its annual operating profit margin, excluding certain items, would be unchanged around 17 percent.
Analysts, on average, are looking for full-year revenue to grow 10 percent to 7.12 billion euros, and for the operating margin, excluding certain items, to be around 23.4 percent, according to the Reuters poll.
Last year, eight out of 10 of the world's top selling electric vehicles were powered by Infineon chips.
Infineon is the top maker of microcontrollers used in the central powertrains of many luxury vehicles, but lags rival chipmakers Renesas, NXP and Texas Instruments in the wider market for car microcontrollers.
($1 = 0.8457 euros) (Reporting By Eric Auchard; Editing by Maria Sheahan)