Last year at Flash Memory Summit, Toshiba announced XL-FLASH, a specialized low-latency SLC 3D NAND flash memory that is their answer to Samsung's Z-NAND (and to a lesser extent, Intel's 3D XPoint). Few details were provided at the time, but this year Toshiba is ready to give out more information, including a timeline for bringing it to market: sampling starts next month, and mass production begins next year.

The first XL-FLASH parts will use a 128Gb die, divided into 16 planes to support a much higher degree of parallelism than existing capacity-oriented 3D NAND parts. The page size will be 4kB, significantly smaller than what most 3D NAND uses, but that's not a surprise given that XL-FLASH is storing just one bit per cell rather than three or four. Toshiba's press release does not disclose the erase block size, but we expect it to be similarly smaller than what's used in high-capacity NAND designs. As for performance, Toshiba says read latency will be less than 5 microseconds, compared to about 50 µs for their 3D TLC.

The most significant difference between Toshiba's XL-FLASH and Samsung's Z-NAND may end up being the business model. Samsung's keeping Z-NAND to themselves for use in their Z-SSD products, but Toshiba's XL-FLASH will be for sale the same as their 3D TLC and QLC NAND. We have already heard from a few SSD controller vendors that they plan to support XL-FLASH in their upcoming controllers, so when XL-FLASH starts to hit the market it will probably be arriving in SSDs from several competing brands.

Flash Memory Summit kicks off tomorrow in Santa Clara, and Toshiba will be giving the first keynote presentation.

Comments Locked


View All Comments

  • Alistair - Monday, August 5, 2019 - link

    Let's go, flash memory summit 2019!
  • danielfranklin - Monday, August 5, 2019 - link

    This is great news.
    There is a major lack of any mainstream options for low latency SSDs and its leads to very high prices. Opening up the market like this could allow to eventually have low latency SSDs that are approaching being priced relative to their die capacity/price.
    Eg. If their dice are 4x the cost per GB, we simply pay double for half capacity. Much better than the other options, particularly when any improvement is appreciated!
  • Santoval - Tuesday, August 6, 2019 - link

    So XL-FLASH is basically the 3D version of the old planar SLC NAND? What about endurance, does it have the very high endurance of planar SLC? Slicing the latency to 1/10 of TLC's latency sounds exciting, though something tells me the price of these SSDs will be too high for us mere mortals.
  • mode_13h - Tuesday, August 6, 2019 - link

    Unless they made the cells smaller, you should at least expect better endurance than TLC!

    I would love to see this stuff in an enthusiast-oriented SSD.
  • urbanman2004 - Tuesday, August 6, 2019 - link

    I see Toshiba's able to bounce back (rebound) quick since losing 6 exobytes for flash nand in the outage.

Log in

Don't have an account? Sign up now