NOR based flash has long erase and write times and has a full address/ data interface.Â Meaning one can read or write data to any portion of the NOR chip.Â The NOR technology is mostly used for low levels of read/write cycles.Â So for example, NOR is great for BIOS and firmware of a device.Â NOR was the first version of flash, but everyone quickly realized a cheaper, faster solution is also needed. In 1989 the first NAND flash chip was introduced.Â It had faster erase and write times, higher density, and lower cost than NOR flash – with ten times the endurance. The draw back with NAND [if you can call it that] is the I/O interface only allowing sequential access to data. Meaning you can only write to the device after the last bit of data has been written.Â This makes it suitable for mass-storage devices such as PC cards and various memory cards like USB, SD and microSD, and somewhat less useful for computer memory. Source:Â TutorialsWeb. Continue Reading 1 Comment
Posts Tagged ‘NAND flash’
The 3-bit per cell concept allows for more storage in the same realestat of flash memory.Â This imporvement yields larger storage capacity of flash drives and SSD at a lower price. However, the new technology doesn’t come without some draw backs.Â According to Kevin Kilbuck, Director of NAND marketing at Micron indicates the 3-bit per cell technology isn’t as stable as they’d like. For example, Kevin indicates the 3-bit per cell NAND technology will be found in less mission critical devices like USB flash drives, SD memory and CF memory.Â The technology will not find it’s way into SolidState Disks until the manufacturing process is perfected.
“The companies explained that they need more experience in production volumes before they will be confident to position it as a chip suitable for the high-write environment of the SSD”You can expect the 3-bit per cell to hit the streets sometime in Q1 of 2010. However, as with most technology, it’s on the way out before it’s ever even in; SanDisk and Toshiba disclosed in February that they had developed 4-bit-per-cell technology, which the two companies said was the highest-capacity flash memory technology in the industry. Continue Reading