Portable embedded systems like mobile handsets demand compact, low-power, robust storage. M-Systems' Mobile DiskOnChip delivers high-performance NAND-based flash memory that interfaces like a memory-mapped disk drive for these types of systems. It works just as well for fixed environments, such as set-top boxes, where size and performance are issues.
The Mobile DiskOnChip provides many of the features found in its larger cousin, the Millennium DiskOnChip. While the Mobile version lacks the Millennium's security protection, it includes the 1-kbyte SRAM boot block whose contents are mirrored in the on-chip 16 Mbytes of flash memory. Up to four chips can be cascaded without the need for external logic for a total of 64 Mbytes.
Its on-chip processing handles error correction and transparent data migration for wear-leveling. The latter keeps putting new data in different physical flash-memory pages. So on average, each physical page is written to occasionally even if the same page of data is being written to continuously. Flash memory supports a finite number of writes to an individual page.
The 63-pin BGA chip is only 9 by 11 by 1.4 mm. Built on a 0.18-µm process, it operates at 1.8 V. Active power consumption is 13 mA. Standby current is 30 µA. Erase time is 3 ms, significantly faster than NOR flash technology.
The Mobile DiskOnChip is available immediately. Contact M-Systems for volume pricing.
M-Systems Inc., 8371 Central Ave., Suite A, Newark, CA 94560; (510) 494-2090; www.m-sys.com.