Updated from 11:47 a.m.Chipmakers grabbed the tech sector's center stage Tuesday, as several companies, including Texas Instruments ( TXN), moved after updating their financial guidance. Diodes ( DIOD) rose 5.4% after the chipmaker lifted its second-quarter revenue guidance. The company now sees sequential revenue growth of 3% to 5%, up from an earlier view of 2% to 5%. The new guidance represents year-over-year revenue growth of 14% to 17%. Diodes posted revenue of $82.7 million during last year's second quarter, which implies revenue of $94.3 million to $96.8 million for this year's second quarter. Analysts polled by Thomson Financial project revenue of $95.2 million. Shares closed up $1.94 to $37.92. Diodes, however, bucked the sector's broader trend. The Nasdaq 100 was trading down about 11 points to about 1891, and several other chipmakers followed suit. Broadcom ( BRCM) traded actively after the chipmaker agreed to acquire privately held GPS technology company Global Locate for about $146 million in cash. "With the acquisition of Global Locate, Broadcom will be the only semiconductor supplier in the world with top-tier customers in Bluetooth, Wi-Fi, FM radio and GPS, four of the key wireless technologies now being added to next generation mobile phones," Broadcom said. If Global Locate reaches certain performance goals, former shareholders will receive up to $80 million in additional cash. Shares of Broadcom closed down 64 cents, or 2.1%, to $30.10. Meanwhile, Texas Instruments fell 2.1% after the chipmaker narrowed its second-quarter guidance. The company now sees earnings of 40 cents to 44 cents a share on revenue of $3.36 billion to $3.51 billion. Previously, the company said that it would earn 39 cents to 45 cents a share on revenue of $3.32 billion to $3.6 billion. Analysts project earnings of 42 cents a share on revenue of $3.46 billion. Shares closed down 75 cents to $35.04. Richardson Electronics ( RELL) fell 1.6% after the company said its chief financial officer David DeNeve resigned to pursue other interests. DeNeve's last day on the job will be June 22. In the meantime, Dan Fujii will serve as interim CFO until a full-time replacement is found. Shares were down 15 cents to $9.20. Finally, Focus Enhancement ( FCSE) slumped 10.4% after the communications company cut its 2007 revenue guidance. The company now sees revenue of $38 million to $40 million, down from an earlier forecast of $42 million to $44 million. Analysts project revenue of $42.3 million. Shares closed down 12 cents to $1.03.