UPDATE 1-Chipmaker Xilinx forecasts weak current-quarter revenue
* Expects 4th-qtr revenue of $598.5-$622 mln vs est $621.1 mln
* Third-quarter EPS $0.61 vs est $0.54
* Revenue $586.8 mln vs est $600.6 mln
* Shares down 4 pct in post-market trading
Jan 21 (Reuters) - Chipmaker Xilinx Inc forecast current-quarter revenue largely below analysts' estimates, hurt by weak sales to telecom, aerospace and defense customers, sending its shares down 4 percent in extended trading.
Xilinx, which also reported lower-than-anticipated sales for the third quarter ended Dec. 28, said it expected revenue in the fourth quarter to increase 2 percent to 6 percent from the third quarter.
That implies current-quarter revenue of $598.5 million to $622 million. Analysts on average were expecting $621.1 million, according to Thomson Reuters I/B/E/S.
The company forecast gross margins of about 68 percent. They were 69.2 percent in the third quarter.
Xilinx's chips are used by the U.S. Air Force and the European Organization for Nuclear Research (CERN), as well as by investors to make high-frequency trades.
High-frequency trading refers to trades based on complex computer-based algorithms that guide decisions on what stocks to buy or sell.
Xilinx's net income jumped 70 percent to $175.9 million, or 61 cents per share, in the third quarter from a year earlier.
The company, which counts Sweden-based Ericsson and Hong Kong-based ZTE Corp among its major customers, reported a 15 percent rise in revenue to $586.8 million.
Xilinx's largest business, communications and data center, remained flat, while its industrial, aerospace & defense business decreased 5 percent.
Analysts on average had expected earnings of 54 cents per share on revenue of $600.6 million, according to Thomson Reuters I/B/E/S.
Xilinx's shares were at $45.70 in extended trading after closing at $47.54 on the Nasdaq on Tuesday.