Date: 01/03/2011

JEDEC publishes standards for flash memory based UFS

JEDEC Solid State Technology Association has announced the publication of its next-gen storage system standard, Universal Flash Storage (UFS). UFS is designed to be the most advanced specification for both embedded and removable flash memory-based storage in mobile devices such as smart phones and tablet computers. The UFS is designed for use in mobile computers and phones and also in computers requiring high performance memory at low power. With an initial data throughput 300 megabytes per second the UFS standards supports command queuing features to raise random read/write speeds. JESD220 Universal Flash Storage standards can be downloaded for free of cost from the JEDEC website http://www.jedec.org/standards-documents/results/jesd220.

On the requirement enhanced storage solution due to increase in mobile content download, JEDEC quotes Gartner's forecast of 117% increase in mobile application downloads in 2011 vs 2010.

UFS is built on the success of another popular flash memory storage standard JEDEC eMMC standard. UFS adopts and enhances mobile features from eMMC in order to manage security, performance and power consumption to a high performance parallel architecture, offering mobile device makers a long term roadmap of standardized mobile flash devices that will meet their system requirements.

UFS is using MIPI Alliance's M-PHY and UniProSM specifications to achieve the highest performance and most power efficient data transport.
.UniPro is for universal chip-to-chip protocol, providing a common tunnel for other protocols. The M-PHY interface is the primary physical interface (PHY layer) for the UniPro specification, and is a high speed serial interface targeting up to 2.9 gigabits per second (Gbps) per lane with up-scalability to 5.8Gbps per lane. Both M-PHY and UniPro specs are optimized for mobile applications with range of features for low consumption.

The UFS standard also adopts the popular SCSI Architecture Model and command protocols supporting multiple commands with command queuing features and enabling a multi-thread programming paradigm. As per JEDEC this differs from conventional flash-based memory cards and embedded flash solutions which process one command at a time, limiting random read/write access performance. JEDEC says the forthcoming complementary UFS Host Controller Interface (HCI) specification will allow system designers greater flexibility by simplifying the involvement of the host processor in the operation of the flash storage subsystem. The UFS HCI specification and the adoption of SCSI will provide a well-known software programming model and enable wider market adoption, according JEDEC.

"The publication of UFS is an important milestone for JEDEC and the Industry, and represents countless hours of collaboration between memory manufacturers and principal consumer device and mobile OEMs," said Mian Quddus, Chairman of the JEDEC Board of Directors and the JC-64 Committee for Flash Memory Modules. He added, "Since UFS provides for both embedded and removable card formats the interface is the same for both, which simplifies controller design - an attractive feature for device designers."

Joel Huloux, Chairman of the MIPI Alliance Board of Directors, said: "MIPI is pleased to have collaborated with JEDEC on the inclusion of M-PHY and UniPro specifications as the interconnect layer for UFS. Together, these standards represent a revolutionary advancement for future mobile device performance."

In addition to UFS development work within JEDEC, some major participants have founded a new organization, the Universal Flash Storage Association (UFSA), to develop an ecosystem and support environment for UFS devices and host applications.

In this month JEDEC also announced that its JC-45 Committee for DRAM modules intends to form a new Subcommittee focused on the standardization of hybrid memory modules.

JEDEC Solid State Technology Association has recently published SSD standards JESD218 and JESD219.