NEC Develops New Clocking Technology with Dynamic Voltage and Frequency Scaling (DVFS) for Further Power Reduction in Multicore System LSI Chips

NEC Develops New Clocking Technology with Dynamic Voltage and Frequency Scaling (DVFS) for Further Power Reduction in Multicore System LSI Chips

SAN FRANCISCO, Feb. 8 /PRNewswire-FirstCall/ -- NEC Corporation (NASDAQ:NIPNY) (FTSE: 6701q.l) today introduced multicore clocking technology, a key technology that realizes low-power multicore large-scale integrated (LSI) chips by optimizing the clock frequency of intellectual property (IP) cores independently during chip operation. This research will be presented at the International Solid-State Circuit Conference (ISSCC) 2005 being held February 7 through 9 in San Francisco.

While LSI performance can be improved by complementary metal-oxide- semiconductor (CMOS) device scaling, power increases resulting from performance enhancement become crucial. Recently, there have been cases where it was not possible to improve LSI performance because of the power consumption limitation, for example, in cellular phones. Low-power technologies such as multicore architecture and dynamic voltage and frequency scaling (DVFS) can solve this power consumption problem in scaled-down CMOS devices.

NEC's clocking technology introduced today is key to independently applying DVFS to each IP core and to enabling an individual unit composed of multiple IP cores to operate at the appropriate voltage and frequency. This clocking technology contains the following new features:

1) A periodically all-in-phase clocking methodology in which local clock
signals for each IP core are periodically generated "all in phase."
2) A core clock generator producing frequencies at finer frequency steps
and with frequency changes more than one thousand times faster than
conventional phase-locked loops (PLLs).



Another notable feature of the new clocking technology is the ability to predefine data communication timing deterministically, by numbering all clock edges individually based on all-in-phase timing. The conventional way of determining clock frequency for each IP core independently makes the intercore data communication asynchronous or nondeterministic. For example, problems such as the discrepancy in output results and timing of each chip occur due to differences in the operating environment and temperature among chips, even though they are made from the same wafer. With the new clocking technology, the intercore communication that is independent of differences in device characteristics, operating environments, output results and timing of each chip does not vary, even though each IP core is operated at a different frequency. Also, overall chip behavior simulated with EDA tools can precisely match actual chip operations, making it easy to facilitate chip verification and testing.

"This clocking technology enables further power reduction in the multicore-based system LSI platform NEC has developed. Our simulation result shows this technology will achieve 60 percent power reduction. We continue to proactively promote technology developments to enhance the multicore-based system LSI platform," said Dr. Masao Fukuma, vice president, R&D Unit, NEC Corporation.

About NEC Corporation

NEC Corporation is one of the world's leading providers of Internet, broadband network and enterprise business solutions dedicated to meeting the specialized needs of its diverse and global base of customers. Ranked as one of the world's top patent-producing companies, NEC delivers tailored solutions in the key fields of computer, networking and electron devices, by integrating its technical strengths in IT and Networks, and by providing advanced semiconductor solutions through NEC Electronics Corporation. The NEC Group employs more than 140,000 people worldwide and had net sales of 4,906 billion yen (approx. $47 billion) in the fiscal year ended March 2004. For additional information, please visit the NEC home page at http://www.nec.com/.


Source: NEC Corporation

CONTACT: In Japan: Diane Foley of NEC Corporation, + 81-3-3798-6511 or
d-foley@ax.jp.nec.com; In the Americas: Denise Viereck Garibaldi of NEC
Electronics America, Inc., +1-408-588-6620 or denise_garibaldi@necelam.com; or
In the Americas: Kazuko Andersen of NEC USA, Inc., +1-212-326-2502 or
kazuko.andersen@necusa.com

Web site: http://www.necel.com/


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