Universal Flash Storage (UFS) is a flash storage specification for

digital camera A digital camera, also called a digicam, is a camera that captures photographs in Digital data storage, digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film or film stock. Dig ...

mobile phone A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This rad ...

s and consumer electronic devices. 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 cards. The standard encompasses both packages permanently embedded (via ball grid array package) within a device (), and removable UFS memory cards.

Overview

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

flash memory Flash memory is an Integrated circuit, electronic Non-volatile memory, non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for t ...

specification is supported by consumer electronics companies such as

Nokia Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally established as a pulp mill in 1 ...

, Sony Ericsson,

Texas Instruments Texas Instruments Incorporated (TI) is an American multinational semiconductor company headquartered in Dallas, Texas. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog ...

, STMicroelectronics,

Samsung Samsung Group (; stylised as SΛMSUNG) is a South Korean Multinational corporation, multinational manufacturing Conglomerate (company), conglomerate headquartered in the Samsung Town office complex in Seoul. The group consists of numerous a ...

, Micron, and SK Hynix. UFS is positioned as a replacement for and SD cards. The electrical interface for UFS uses the M-PHY, 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. UFS implements a full-duplex serial LVDS interface that scales better to higher bandwidths than the 8-lane parallel and half-duplex interface of . Unlike eMMC, Universal Flash Storage is based on the SCSI architectural model and supports SCSI Tagged Command Queuing. The standard is developed by, and available from, the JEDEC Solid State Technology Association.

Software support

The

Linux kernel The Linux kernel is a Free and open-source software, free and open source Unix-like kernel (operating system), kernel that is used in many computer systems worldwide. The kernel was created by Linus Torvalds in 1991 and was soon adopted as the k ...

supports UFS. OpenBSD 7.3 and later support UFS.

Windows 10 Windows 10 is a major release of Microsoft's Windows NT operating system. The successor to Windows 8.1, it was Software release cycle#Release to manufacturing (RTM), released to manufacturing on July 15, 2015, and later to retail on July 2 ...

and later support UFS.

History

In 2010, the Universal Flash Storage Association (UFSA) was founded as an open

trade association A trade association, also known as an industry trade group, business association, sector association or industry body, is an organization founded and funded by businesses that operate in a specific Industry (economics), industry. Through collabor ...

to promote the UFS standard. 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,

unveiled embedded UFS () v3.0 and uMCP (UFS-based multi-chip package) solutions. On 30 January 2020 JEDEC published version 3.1 of the UFS standard. 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. Before the UFS 3.1 standard, the SLC cache feature is optional on UFS device, which is a de facto feature on personal SSDs. In 2022 Samsung announced version 4.0 doubling from 11.6 Gbit/s to 23.2 Gbit/s with the use of MIPI M-PHY v5.0 and UniPro v2.0. UFS 4.0 introduces File Based Optimization. As of Q2 2024, Zoned UFS (ZUFS) is in development by SK hynix.

Notable devices

In February 2013, semiconductor company Toshiba Memory (now Kioxia) started shipping samples of a 64 GB NAND flash chip, the first chip to support the then new UFS standard. In April 2015, Samsung's Galaxy S6 family was the first phone to ship with storage using the UFS 2.0 standard. On 17 November 2016,

Qualcomm Qualcomm Incorporated () is an American multinational corporation headquartered in San Diego, California, and Delaware General Corporation Law, incorporated in Delaware. It creates semiconductors, software and services related to wireless techn ...

announced the

Snapdragon 835 The Qualcomm Snapdragon suite of System on a chip, systems on chips (SoCs) are designed for use in smartphones, Tablet computer, tablets, laptops, 2-in-1 PCs, smartwatches, and smartbooks devices. Before Snapdragon SoC made by Qualcomm before ...

SoC with support for UFS 2.1. On 14 May 2019, OnePlus introduced the OnePlus 7 and OnePlus 7 Pro, the first phones to feature built-in 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). On 08 December 2022, IQOO announced the IQOO 11 which was the first phone to release with UFS 4.0. After that, other Android OEMs started using this storage solution on their flagship to upper mid-range category smartphones.

UFS cards

On 7 July 2016, Samsung announced its first UFS cards, in 32, 64, 128, and 256 GB storage capacities. The cards were based on the UFS 1.0 Card Extension Standard. The 256 GB 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. However, they were apparently not actually released to the public. The first UFS cards began to be publicly sold in early 2020. According to a Universal Flash Storage Association press release, Samsung planned to transition its products to UFS cards during 2020. Samsung states that its UFS card is only supported by models of its Samsung Notebook. The 2021 LG Gram notebook also supports UFS cards.

Version comparison

UFS

UFS Card

Implementation

* UFS 2.0 has been implemented in Snapdragon 820 and 821. Kirin 950 and 955. Exynos 7420. NVIDIA Jetson AGX Xavier SOMs * UFS 2.1 has been implemented in Snapdragon 712 (710&720G), 730G, 732G, 835, 845 and 855. Kirin 960, 970 and 980. Exynos 9609, 9610, 9611, 9810 and 980. * UFS 3.0 has been implemented in Snapdragon 855, 855+, 860, 865, Exynos 9820–9825, and Kirin 990. * UFS 3.1 has been implemented in Snapdragon 855+/860, Snapdragon 865, Snapdragon 870, Snapdragon 888, Exynos 2100, and Exynos 2200. * UFS 4.0 has been implemented in MediaTek Dimensity 9200, MediaTek Dimensity 8300 and Snapdragon 8 Gen 2.

Complementary UFS standards

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. Also in March 2016, JEDEC published version 1.1 of the UFS Unified Memory Extension (JESD220-1A), version 2.1 of the UFS Host Controller Interface (UFSHCI) standard (JESD223C), and version 1.1A of the UFSHCI Unified Memory Extension standard (JESD223-1A). On January 30, 2018, the UFS Card Extension standard was updated to version 1.1 (JESD220-2A), and the UFSHCI standard was updated to version 3.0 (JESD223D), to align with UFS version 3.0.

Rewrite cycle life

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. This is typical of flash memory in general. For example, high-end smartphones, and devices such as

set-top box A set-top box (STB), also known as a cable converter box, cable box, receiver, or simply box, and historically television decoder or a converter, is an information appliance device that generally contains a Tuner (radio)#Television, TV tuner inpu ...

es may adopt UFS flash with high terabytes written.https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/collateral/product-brief/product-brief-connected-home-inand-ch-em133-western-digital.pdf

References

External links

JEDEC

Universal Flash Storage Association

Current standards
of UFS and UFS Card
Presentation
by Scott Jacobson and Harish Verma at Flash Memory Summit 2013
What is UFS 2.1 smartphone?
{{Memory Cards Solid-state computer storage Computer-related introductions in 2016