* Nikkei gains 0.15 pct, Topix rises 0.46 pct
* Tech shares track gains by their U.S. peers
* Nikkei extends winning streak, but capped below 23,000 threshold
By Shinichi Saoshiro
TOKYO, Aug 29 (Reuters) - Japan's Nikkei share average rose for the seventh straight session on Wednesday as technology shares advanced along with their Wall Street counterparts.
The Nikkei ended the day up 0.15 percent at 22,848.22 points.
Tokyo Electron rose 0.87 percent, Advantest Corp added 1.95 percent, SUMCO Corp advanced 1.49 percent and Screen Holdings climbed 2.38 percent.
Overall market gains were limited, however. The Nikkei's run has put the benchmark index into overbought territory on the technical charts and it is facing resistance at 23,000, a level last seen in mid-June. It had briefly topped that mark on Tuesday before falling back.
"The Nikkei is top-heavy as profit-taking tends to kick in at these levels. The market, after all, has been rising for several days and the 23,000 mark is proving to be a tough level to overcome," said Takashi Hiroki, chief strategist at Monex Securities.
"For the Nikkei to break and remain above the 23,000 mark, trade conflict concerns will have to subside more convincingly. While recent NAFTA talks have helped, the United States and China will have to resolve their trade dispute to convincingly ease market concerns."
Japanese automakers were mixed, with North American Free Trade Agreement (NAFTA) revision deal between the United States and Mexico expected to affect the regional strategies of non-U.S. car manufacturers.
Toyota Motor Corp was up 0.63 percent, Mazda Motor Corp slipped 0.42 percent and Nissan Motor Co inched down 0.05 percent. Honda Motor Co gained 0.53 percent.
Sources told Reuters on Tuesday that the proposed U.S.-Mexico deal would allow Washington to impose punitive tariffs of up to 25 percent on imports of Mexican-made vehicles above certain volumes. Concerns are that Washington could use such tariffs to win concessions from the European Union and Japan as well.
Bunka Shutter Co was down more than 8 percent after the maker of shutters and building materials announced that it will issue 10 billion yen ($90.51 million) worth of convertible bonds.
Es-con Japan Ltd soared 20.92 percent after the real estate operator said it will form a business and capital alliance with Chubu Electric Power Co.
Surveying software developer Aisan Technology Co jumped 20.48 percent after it announced a business tie-up with telecommunications company KDDI Corp to cooperate in the automatic driving business.
Of Tokyo's 33 sub-indexes, 30 closed the day in positive territory.
The broader Topix gained 0.46 percent to 1,739.60. ($1 = 110.4900 yen) (Reporting by Shinichi Saoshiro; Editing by Kim Coghill)