Universal Flash Storage (UFS) is a

flash storage Flash memory is an electronic 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 the NOR and NAND logic gates. Both use ...

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 Consumer electronics, also known as home electronics, are electronic devices intended for everyday household use. Consumer electronics include those used for entertainment, communications, and recreation. Historically, these products were refer ...

devices. It was designed to bring higher

data transfer Data communication, including data transmission and data reception, is the transfer of data, transmitted and received over a point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optical ...

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 A ball grid array (BGA) is a type of surface-mount packaging (a chip carrier) used for integrated circuits. BGA packages are used to permanently mount devices such as microprocessors. A BGA can provide more interconnection pins than can be pu ...

package) within a device (), and removable UFS

memory card A memory card is an electronic data storage device used for storing digital information, typically using flash memory. These are commonly used in digital portable electronic devices, such as digital cameras as well as in many early games conso ...

Overview

UFS uses

NAND flash 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 ...

. 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 Sony Mobile Communications Inc., originally Sony Ericsson Mobile Communications AB, was a Multinational corporation, multinational consumer electronics and telecommunications company, best known for its Mobile phones, mobile phone products. The ...

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 STMicroelectronics Naamloze vennootschap, NV (commonly referred to as ST or STMicro) is a European multinational corporation, multinational semiconductor contract manufacturing and design company. It is the largest of such companies in Europe. ...

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 The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a uni ...

, and

SK Hynix SK Hynix Inc. () is a South Korean supplier of dynamic random-access memory (DRAM) chips and flash memory chips. SK Hynix is one of the world's largest semiconductor vendors. Founded as Hyundai Electronics in 1983, SK Hynix was integrated into ...

. UFS is positioned as a replacement for and

SD cards Secure Digital (SD) is a proprietary, non-volatile, flash memory card format developed by the SD Association (SDA). Owing to their compact size, SD cards have been widely adopted in a variety of portable consumer electronics, including digit ...

. The electrical interface for UFS uses the

M-PHY M-PHY is a high speed data communications physical layer protocol standard developed by the MIPI Alliance, PHY Working group, and targeted at the needs of mobile multimedia devices. The specification's details are proprietary to MIPI member orga ...

, developed by the

MIPI Alliance MIPI Alliance is a global business alliance that develops technical specifications for the Mobile computing, mobile ecosystem, particularly smart phones but including mobile-influenced industries. MIPI was founded in 2003 by ARM Holdings, Arm, I ...

, 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 Low-voltage differential signaling (LVDS), also known as TIA/EIA-644, is a technical standard that specifies electrical characteristics of a differential, serial signaling standard. LVDS operates at low power and can run at very high speeds u ...

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 {{No footnotes, date=May 2025 The SCSI architectural model provides an abstract view of the way that SCSI devices communicate. It is intended to show how the different SCSI standards are inter-related. The main concepts and terminology of the SCSI ...

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 OpenBSD is a security-focused operating system, security-focused, free software, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by fork (software development), forking NetBSD ...

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 Write amplification (WA) is an undesirable phenomenon associated with flash memory and solid-state drives (SSDs) where the actual amount of information physically written to the storage media is a multiple of the logical amount intended to be wr ...

feature is optional on UFS device, which is a de facto feature on personal

SSD A solid-state drive (SSD) is a type of solid-state storage device that uses Integrated circuit, integrated circuits to store data persistence (computer science), persistently. It is sometimes called semiconductor storage device, solid-stat ...

s. 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 SK Hynix Inc. () is a South Korean supplier of dynamic random-access memory (DRAM) chips and flash memory chips. SK Hynix is one of the world's largest semiconductor vendors. Founded as Hyundai Electronics in 1983, SK Hynix was integrated into ...

Notable devices

In February 2013, semiconductor company Toshiba Memory (now

Kioxia Kioxia Holdings Corporation () is a Japanese multinational computer memory manufacturer headquartered in Tokyo, Japan. The company was spun off from the Toshiba conglomerate in June 2018 and gained its current name in October 2019; it is curren ...

) started shipping samples of a 64 GB

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 SOC, SoC, Soc, may refer to: Science and technology * Information security operations center, in an organization, a centralized unit that deals with computer security issues * Selectable output control * Separation of concerns, a program design pr ...

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 The Samsung Exynos (stylized as SΛMSUNG Exynos), formerly Hummingbird (), is a series of ARM architecture, Arm-based System on a chip, system-on-chips developed by Samsung Electronics' System LSI division and manufactured by Samsung Foundry. I ...

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