Japan's Nikkei hits 1-week low as chipmakers and banks retreat

* Nikkei drops 0.65 pct, Topix loses 0.84 pct

* Chipmakers track drop by U.S. peers

* Banks sag after Mizuho Financial Group slashes profit outlook

* Renesas tumbles after production halt at 6 plants

By Ayai Tomisawa and Shinichi Saoshiro

TOKYO, March 7 (Reuters) - Japan's Nikkei hit a one-week low on Thursday, with chip-related stocks tracking a decline in their U.S. peers and banks retreating after Mizuho Financial Group slashed its profit outlook.

The Nikkei share average ended down 0.65 percent at 21,456.01 after going as low as 21,402.12, its weakest since Feb. 28.

With Wall Street slipping for a third straight day overnight, Japan's markets also succumbed to selling pressure having risen to a three-month high earlier in the week.

"Profit-taking makes sense now as ongoing U.S.-China trade talks, major concerns for the market, have provided no signs of exit plan while the market had risen smoothly for the past two months," said Hikaru Sato, a senior technical analyst at Daiwa Securities.

Chip equipment manufacturers Advantest Corp and Tokyo Electron retreated 2.4 percent and 2.9 percent, respectively. Silicon products maker Sumco Corp slid 6.1 percent.

Japanese high-tech companies sank as the Philadelphia semiconductor index fell for the second day in a row on Wednesday, led by slumping Micron.

Micron fell after Cleveland Research cut this fiscal year's earnings per share and revenue estimates for the semiconductor manufacturer due to weaker-than-expected DRAM and NAND pricing feedback for the first and second quarters.

Of the 33 subsectors at the Tokyo Stock Exchange, 28 ended the day in the red, with non-ferrous metals and banking suffering sizable losses.

Banks retreated after Mizuho Financial Group slashed its full-year profit outlook by 86 percent, citing one-time restructuring costs of 680 billion yen ($6 billion) at its bank and brokerage units and an overhaul of its securities portfolio.

Mizuho Financial Group lost 1.5 percent, Mitsubishi UFJ Financial Group retreated 1.6 percent and Sumitomo Mitsui Financial Group shed 1.7 percent.

Renesas Electronics tumbled 14.6 percent to a daily limit-low of 584 yen on news that the automotive chipmaker is planning to halt production at six Japanese plants for up to two months this year. It was the biggest percentage loser on the board.

The broader Topix dropped 0.84 percent to 1,601.66.

(Editing by Sam Holmes)