Universal Flash Storage

Universal Flash Storage (UFS) is a flash storage specification for digital cameras, mobile phones and consumer electronic devices.[1][2] It was designed to bring higher data transfer speed and increased reliability to flash memory storage, while reducing market confusion and removing the need for different adapters for different types of card.[3]

OverviewEdit

UFS uses NAND flash. It may use multiple stacked 3D TLC NAND flash dies (integrated circuits) with an integrated controller.[4]

The proposed flash memory specification is supported by consumer electronics companies such as Nokia, Sony Ericsson, Texas Instruments, STMicroelectronics, Samsung, Micron, and SK Hynix.[5] UFS is positioned as a replacement for eMMCs and SD cards. The electrical interface for UFS uses the M-PHY,[6] developed by the MIPI Alliance, a high-speed serial interface targeting 2.9 Gbit/s per lane with up-scalability to 5.8 Gbit/s per lane.[7][8] UFS implements a full-duplex serial LVDS interface that scales better to higher bandwidths than the 8-lane parallel interface of eMMCs. Unlike eMMC, Universal Flash Storage is based on the SCSI architectural model and supports SCSI Tagged Command Queuing.[9] The standard is developed by, and available from, the JEDEC Solid State Technology Association.

The Linux kernel supports UFS.[10]

HistoryEdit

In 2010, the Universal Flash Storage Association (UFSA) was founded as an open Trade Association to promote the UFS standard.[11]

In September 2013, JEDEC published JESD220B UFS 2.0 (update to UFS v1.1 standard published in June 2012). JESD220B Universal Flash Storage v2.0 offers increased link bandwidth for performance improvement, a security features extension and additional power saving features over the UFS v1.1.

On 30 January 2018 JEDEC published version 3.0 of the UFS standard, with a higher 11.6 Gbit/s data rate per lane (1450 MB/s) with the use of MIPI M-PHY v4.1 and UniProSM v1.8. At the MWC 2018, Samsung unveiled embedded UFS (eUFS) v3.0 and uMCP solutions.[12][13][14]

On 30 January 2020 JEDEC published version 3.1 of the UFS standard.[15] UFS 3.1 introduces Write Booster, Deep Sleep, Performance Throttling Notification and Host Performance Booster for faster, more power efficient and cheaper UFS solutions. The Host Performance Booster feature is optional.[16]

Notable devicesEdit

In February 2013, semiconductor company Toshiba Memory (now Kioxia) started shipping samples of a 64GB NAND flash chip, the first chip to support the then new UFS standard.[17]

In April 2015, Samsung's Galaxy S6 family was the first phone to ship using the UFS (Universal Flash Storage) 2.0 standard.[18]

On 7 July 2016, Samsung introduced its first UFS cards, in 32, 64, 128, and 256 GB storage capacities.[19] The cards were based on the UFS 1.0 Card Extension Standard. The 256GB version was reported to offer sequential read performance up to 530 MB/s and sequential write performance up to 170 MB/s and random performance of 40,000 read IOPS and 35,000 write IOPS.

On 17 November 2016, Qualcomm announced the Snapdragon 835 SoC with support for UFS 2.1. The Snapdragon 835 also supports SD Card Version 3.0 and USB 3.1 Type-C.[20]

On 14 May 2019, OnePlus introduced the OnePlus 7 and OnePlus 7 Pro, the first phones to feature built-in UFS 3.0 (The Galaxy Fold, originally planned to be the first smartphone to feature UFS 3.0 was ultimately delayed after the OnePlus 7's launch).[21]

Version comparisonEdit

UFSEdit

UFS 1.0 1.1 2.0 2.1 3.0[22][23] 3.1
Introduced 2011-02-24[24] 2012-06-25[25] 2013-09-18[26] 2016-04-04[27] 2018-01-30[28] 2020-01-30[29]
Bandwidth per lane 300 MB/s 600 MB/s 1450 MB/s
Max. number of lanes 1 2
Max. total bandwidth 300 MB/s 1200 MB/s 2900 MB/s
M-PHY version ? ? 3.0 4.1
UniPro version ? ? 1.6 1.8

UFS CardEdit

UFS Card 1.0 1.1 2.0
Introduced 2016-03-30[30] 2018-01-30[28] 2018-09-18[31]
Bandwidth per lane 600 MB/s 1200 MB/s
Max. number of lanes 1
Max. total bandwidth 600 MB/s 1200 MB/s
M-PHY version 3.0 ?
UniPro version 1.6 ?

ImplementationEdit

UFS 2.0 in Snapdragon 820 and 821. Kirin 950 and 955. Exynos 7420

UFS 2.1 in Snapdragon 712(710&720G), 730G, 835, 845 and 850. Kirin 960, 970 and 980. Exynos 9609,[32] 9610,[33] 9611,[34] 9810 and 980.[35]

UFS 3.0 in Snapdragon 855. Exynos 9820/9825,[36] and Kirin 990.[37]

Complementary UFS standardsEdit

On 30 March 2016, JEDEC published version 1.0 of the UFS Card Extension Standard (JESD220-2), which offered many of the features and much of the same functionality as the existing UFS 2.0 embedded device standard, but with additions and modifications for removable cards.[38]

Also in March 2016, JEDEC published version 1.1 of the UFS Unified Memory Extension (JESD220-1A),[39] version 2.1 of the UFS Host Controller Interface (UFSHCI) standard (JESD223C),[40] and version 1.1A of the UFSHCI Unified Memory Extension standard (JESD223-1A).[41]

On January 30, 2018, the UFS Card Extension standard was updated to version 1.1 (JESD220-2A),[42] and the UFSHCI standard was updated to version 3.0 (JESD223D), to align with UFS version 3.0.[43]

Rewrite cycle lifeEdit

A UFS drive's rewrite life cycle affects its lifespan. There is a limit to how many write/erase cycles a flash block can accept before it produces errors or fails altogether. Each write/erase cycle causes a flash memory cell's oxide layer to deteriorate. The reliability of a drive is based on three factors: the age of the drive, total terabytes written over time and drive writes per day.[44]

See alsoEdit

ReferencesEdit

  1. ^ "Nokia, Others Back Mobile Memory Standard". PC World. Archived from the original on 9 February 2008.
  2. ^ JEDEC Announces Publication of Universal Flash Storage (UFS) Standard
  3. ^ Malykhina, Elena (14 September 2007). "Mobile Tech Companies Work On Flash Memory Standard". Information Week. Archived from the original on 12 September 2012. Retrieved 19 September 2012.
  4. ^ "Toshiba Begins to Sample UFS 3.0 Drives: 96L 3D TLC NAND, Up to 2.9 GB/s". Anandtech. 23 January 2019. Retrieved 18 August 2020.
  5. ^ Modine, Austin (14 September 2007). "Flash memory makers propose common card". The Channel. Retrieved 19 September 2012.
  6. ^ "Archived copy". Archived from the original on 28 September 2011. Retrieved 15 August 2011.CS1 maint: archived copy as title (link)
  7. ^ http://www.mipi.org/
  8. ^ "Archived copy". Archived from the original on 22 December 2015. Retrieved 26 October 2015.CS1 maint: archived copy as title (link)
  9. ^ "Universal Flash Storage: Mobilize Your Data". Design Reuse. Retrieved 18 August 2020.
  10. ^ https://www.kernel.org/doc/Documentation/scsi/ufs.txt
  11. ^ "Organization: Universal Flash Storage Association". Crunchbase. Retrieved 18 August 2020.
  12. ^ "Evolving Mobile Solutions: Samsung at MWC 2018 | Samsung Semiconductor Global Website". www.samsung.com.
  13. ^ "eUFS | Samsung Semiconductor Global Website". www.samsung.com.
  14. ^ "Samsung Starts Producing First 512-Gigabyte Universal Flash Storage for Next-Generation Mobile Devices | Samsung Semiconductor Global Website". www.samsung.com.
  15. ^ "JEDEC Publishes Update to Universal Flash Storage (UFS) Standard | JEDEC". www.jedec.org. Retrieved 31 January 2020.
  16. ^ Shilov, Anton. "Faster, Cheaper, Power Efficient UFS Storage: UFS 3.1 Spec Published". www.anandtech.com. Retrieved 1 February 2020.
  17. ^ "Toshiba ships first NAND flash chips with faster transfer standard". PC World. 8 February 2013. Retrieved 18 August 2020.
  18. ^ "The Samsung Galaxy S6 and S6 edge Review". Anandtech. 17 April 2015. Retrieved 18 August 2020.
  19. ^ Shilov, Anton. "Samsung Rolls Out Its First UFS Cards: SSD Performance in Card Form-Factor". Retrieved 7 July 2016.
  20. ^ "Qualcomm Snapdragon 865 to sport LPDDR5X RAM, UFS 3.0, will come in 2 variants: Report". First Post. 18 June 2019. Retrieved 18 August 2020.
  21. ^ "OnePlus 7 Pro confirmed to feature UFS 3.0 flash storage". Android Central. 6 May 2019. Retrieved 18 August 2020.
  22. ^ Cho, HeeChang (August 2016). "Next Generation of Mobile Storage: UFS and UFS Card" (PDF). Jedec.
  23. ^ Chen, Horace (July 2017). "UFS 3.0 Controller Design Considerations" (PDF). Jedec. Archived from the original (PDF) on 7 November 2017.
  24. ^ "JEDEC Announces Publication of Universal Flash Storage (UFS) Standard | JEDEC". www.jedec.org. Retrieved 8 May 2017.
  25. ^ "JEDEC Updates Universal Flash Storage (UFS) Standard | JEDEC". www.jedec.org. Retrieved 8 May 2017.
  26. ^ "JEDEC Publishes Universal Flash Storage (UFS) Standard v2.0 | JEDEC". www.jedec.org. Retrieved 8 May 2017.
  27. ^ "JEDEC Updates Universal Flash Storage (UFS) and Related Standards | JEDEC". www.jedec.org. Retrieved 8 May 2017.
  28. ^ a b "JEDEC Publishes Universal Flash Storage (UFS & UFSHCI) Version 3.0 and UFS Card Extension Version 1.1 | JEDEC". www.jedec.org. Retrieved 31 January 2018.
  29. ^ "JEDEC Publishes Update to Universal Flash Storage (UFS) Standard | JEDEC". www.jedec.org. Retrieved 31 January 2020.
  30. ^ "JEDEC Publishes Universal Flash Storage (UFS) Removable Card Standard | JEDEC". www.jedec.org. Retrieved 30 October 2017.
  31. ^ "JEDEC Publishes Universal Flash Storage (UFS) Standard v2.0 | JEDEC". www.jedec.org. Retrieved 1 February 2020.
  32. ^ "Exynos 9609 Mobile Processor: Specs, Features | Samsung Exynos". Samsung Semiconductor. Retrieved 26 January 2020.
  33. ^ "Exynos 9610 Processor: Specs, Features | Samsung Exynos". Samsung Semiconductor. Retrieved 26 January 2020.
  34. ^ "Exynos 9611 Mobile Processor: Specs, Features | Samsung Exynos". Samsung Semiconductor. Retrieved 26 January 2020.
  35. ^ "Exynos 980 5G Mobile Processor: Specs, Features | Samsung Exynos". Samsung Semiconductor. Retrieved 26 January 2020.
  36. ^ "Exynos 9 Series 9820 Processor: Specs, Features | Samsung Exynos". Samsung Semiconductor. Retrieved 14 November 2018.
  37. ^ Cutress, Ian (6 September 2019). "Huawei Announces Kirin 990 and Kirin 990 5G: Dual SoC Approach, Integrated 5G Modem". AnandTech. Archived from the original on 6 September 2019.
  38. ^ "JEDEC Publishes Universal Flash Storage (UFS) Removable Card Standard | JEDEC". www.jedec.org. Retrieved 7 July 2016.
  39. ^ Universal Flash Storage - Unified Memory Extension Version 1.1
  40. ^ Universal Flash Storage Host Controller Interface (UFSHCI), Version 2.1
  41. ^ Universal Flash Storage Host Controller Interface Unified Memory Extension, Version 1.1A
  42. ^ Universal Flash Storage Card Extension, Version 1.1
  43. ^ Universal Flash Storage (UFS) - JEDEC
  44. ^ "SSD Lifespan: How Long Will Your SSD Work?". Enterprise Storage Forum. 1 March 2019. Retrieved 18 August 2020.

External linksEdit