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Third Party Bandwidth Requirements Illustrate that MLC NAND Meets the Read/Write Speed and Data Integrity Requirements of Consumer Electronics Applications

IRVINE, Calif., May 10, 2004 -- In an effort to increase its customers' knowledge of NAND-based storage products, Toshiba America Electronic Components, Inc. (TAEC)* has published an application note titled, "MLC NAND Performance for Consumer Applications," which provides performance characteristics for both single-level cell (SLC) and multi-level cell (MLC) NAND Flash memory. It also includes information on bandwidth requirements for many typical consumer applications, from playing music to streaming digital video. Based on the results of the study, TAEC announced that its latest multi-level cell (MLC) NAND Flash memory chips surpass the reliability and performance requirements of most consumer electronics applications.

The increased bandwidth of the company's latest MLC NAND Flash, developed by Toshiba Corp. (Toshiba), exceeds the minimum read and write requirements of some file formats by as much as a factor of 20, going beyond the necessary functionality and reliability for the majority of today's consumer electronics applications. Toshiba recently introduced the semiconductor industry's first 4-gigabit1 (Gb) single-die MLC NAND Flash device, produced with 90-nanometer (nm) process technology. The new high-density memory device enables faster write performance by implementing advanced design concepts and adjusting the control system of the memory cell.

Based on extensive internal and external testing by TAEC, combined with published bandwidth requirements for various digital video and music formats, Toshiba's MLC NAND devices can offer more than sufficient performance to support the minimum read-and-write specifications of various digital video file formats, including MPEG2, MPEG4 Advanced Video Coding (AVC) or H.264, Windows Media® 9.0 files; standard digital audio file formats, including MP3 and WMA files; and a range of Microsoft® Office applications, including Excel, Word, and PowerPoint® files.

"Toshiba offers both SLC and MLC NAND Flash to provide a range of value and performance solutions for our customers. For many consumer applications, including MP3 players, many digital camcorders, digital cameras and USB drives, we have found that MLC NAND Flash provides a reliable, cost efficient solution to meet the increasing densities that will enable new applications," said Scott Nelson, business development director for memory products at TAEC.

Nelson continued, "This data illustrates that MLC NAND Flash is well suited for a host of different applications, delivering more than sufficient read and write performance and reliability for office productivity, digital video, and digital audio files. The increased write speed offered by Toshiba's latest generation 90nm chips further extends the range of applications for MLC NAND Flash in memory cards and USB drives. As a result, our customers and consumers can feel completely confident in using MLC NAND-based products, which in many cases can provide a better performance/value choice than SLC NAND."

TOSHIBA MLC NAND Powers DVD-Quality Digital Video Applications
Toshiba's latest MLC NAND Flash devices deliver read and write times of 108 megabits2 per second (Mb/s) and 20 Mb/s, respectively. This is more than sufficient to support DVD quality video applications, which require a bandwidth of 6Mb/s to 8Mb/s for MPEG2, 720 x 480 digital video3, 2Mb/s to 4Mb/s for Windows Media 9 digital video3, and 3Mb/s to 4Mb/s for H.264/MPEG4 720 x 480 digital video4. MLC NAND Flash also meets or exceeds the bandwidth requirements for high definition (HD) DVD video, which are 19Mb/s to 20Mb/s for MPEG2, 1280x720 video3, 5Mb/s to 8Mb/s for Windows Media 9 1280 x 720 video3, and 6Mb/s to 7Mb/s for H.64/MPEG4 1280 x720 video5.

Cost-effective Storage for Digital Music
Storing and playing digital music is another application for which Toshiba MLC NAND Flash is well suited and offers a cost-effective solution. The minimum bandwidth to play either MP35 or WMA5 files is approximately 128 kilobits6/second (kbps), a small fraction of the 108Mb/s read speed of Toshiba large block MLC NAND. A typical MP3 song is about 4 megabytes7 (MB) of memory. With the MLC write speed of 20Mb/sec (2.5MB per second (MB/s)), it takes less than 2 seconds to download a song. As a result, the specifications of Toshiba MLC NAND Flash technology exceed those required for the downloading and playback of digital music.

Office Application Data Storage Performance
For typical office applications, such as Microsoft Office, Excel, PowerPoint and Word, Toshiba MLC NAND Flash can deliver sufficient bandwidth for the reading and writing of these files, demonstrating that MLC performance is suitable for MLC NAND-based USB drives. Expressed in megabytes per second, the read and write speeds of Toshiba large block MLC NAND are 13.55 MB/s and 2.5 MB/s, respectively.

To test the time required to download typical size Word, Excel and PowerPoint files, TAEC simulated files stored on its servers, determining the media, average and maximum file sizes for each application to get a typical representation of documents in an enterprise environment. The average size documents were 159 kilobytes (kB), 528kB, and 1.18MB, respectively, for Word, Excel and PowerPoint documents. For these documents, the time required to read the average Word, Excel, and Power point document is less than a second, which is more than sufficient to satisfy today's consumer and business users of USB Flash Drives for business applications. Details on the median and maximum sized documents can be found in the application note titled "MLC NAND Performance for Consumer Applications" at

Excellent Reliability for Consumer Applications
Contrary to some industry perceptions, MLC NAND Flash offers excellent reliability for consumer applications, even though MLC NAND has a lower rating for the number of write/erase cycles compared to SLC NAND. Currently, Toshiba SLC NAND Flash is rated to have approximately 100,000 cycles, while Toshiba MLC NAND Flash is rated to have approximately 10,000 cycles. While there are applications for which SLC NAND is better suited, the 10,000 cycles of MLC NAND is more than sufficient for a wide range of consumer applications, from storing documents to digital photos. For example, if a 256MB MLC NAND Flash-based card can typically store 250 pictures from a 4-megapixel camera (a conservative estimate), its 10,000 write/erase cycles, combined with wear-leveling algorithms in the controller, will enable the user to store and/or view approximately 2.5 million pictures within the expected useful life of the card. This number is so far beyond the average number of photos taken by the typical user that the difference in endurance between MLC NAND and SLC NAND is not a significant factor for this application. For a more general application such as a USB drive, the 10,000 write/erase cycles would enable the user to completely write and erase the entire contents once per day for 27 years, well beyond the life of the hardware

Recommended Applications for MLC NAND and SLC NAND
MLC NAND Flash provides a very competitive level of performance and makes high-density NAND cards more affordable, enabling new applications that have resulted in growing popularity among consumers. While SLC NAND Flash is more appropriate for some specific, high-performance applications, this difference in performance will not affect the many common consumer applications, including most digital camera users.

Typical applications that are well suited for MLC NAND include digital video and digital still camera memory cards, USB Flash Drives, MP3 players, automobile diagnostics, GPS devices, animatronics, video game cards and toy applications. Applications that may be suited for either MLC NAND or SLC NAND technology include memory cards for printers (fonts), cell phones, telecom applications, voice mail and set-top boxes. SLC NAND Flash is better suited for applications that require speed, and perform many write/erase cycles that require high endurance and high reliability, such as solid state hard disk drives, seismic data recording, networking, HDTV, bar code scanners, ruggedized PCs, flight recorders, and handheld code storage devices as well as embedded NAND in personal digital assistants (PDAs) and digital still cameras. (See Fig. 1. SLC/MLC Applications).

*About TAEC
Combining quality and flexibility with design engineering expertise, TAEC brings a breadth of advanced, next-generation technologies to its customers. This broad offering includes semiconductors, flash memory-based storage solutions, and displays for the computing, wireless, networking, automotive and digital consumer markets.

TAEC is an independent operating company owned by Toshiba America, Inc., a subsidiary of Toshiba, one of the five largest semiconductor companies worldwide in terms of global sales for the year 2003 according to Gartner/Dataquest's Worldwide Semiconductor Market Share Ranking. Toshiba is a world leader in high-technology products with more than 300 major subsidiaries and affiliates worldwide. For additional company and product information, please visit TAEC's website at For technical inquiries, please e-mail

1 When used herein, gigabit and/or Gb means 1,024x1,024x1,024 = 1,073,741,824 bits. Usable capacity may be less. For details, please refer to specifications.
2 When used herein, megabit and/or Mb means 1,024x1,024 = 1,048,576 bits. Usable capacity may be less. For details, please refer to specifications.
3 Microsoft Windows Media 9
4 "Overview of the H.264/AVC Video Coding Standard," IEEE Transactions on Contents on Circuits and Systems for Video Technology, July 2003.
5 "Sand Video Offers H.264 Decoder Core Licenses, EE Times UK, July 21 2003.
7 When used herein, kilobit and/or kb means 1,024 bits. Usable capacity may be less. For details, please refer to specifications.
8 When used herein, megabyte and/or MB means 1,024x1,024 = 1,048,576 bytes. Usable capacity may be less. For details, please refer to specifications. Microsoft, Windows, Microsoft Office, Microsoft Word, PowerPoint, Excel and Windows Media9 are registered trademarks of Microsoft Corporation.

Information in this press release, including product pricing and specifications, content of services and contact information, is current on the date of the announcement, but is subject to change without prior notice. Technical and application information contained here is subject to the most recent applicable Toshiba product specifications. In developing designs, please ensure that Toshiba products are used within specified operating ranges as set forth in the most recent Toshiba product specifications and the information set forth in Toshiba's "Handling Guide for Semiconductor Devices," or "Toshiba Semiconductor Reliability Handbook." This information is available at, or from your TAEC representative.

All other trademarks or registered trademarks are the property of their respective holders.

Figure 1. SLC/MLC Applications

SLC/MLC Applications

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