LONDON – JEDEC Solid State Technology Association, formerly known as the Joint Electron Devices Engineering Council, has published a standard on the use of flash memory for solid-state storage in mobile devices such as smart phones and tablet computers.
The Universal Flash Storage (UFS) standard covers both embedded and removable flash memory-based storage. It builds on the e.MMC standard and adds features for security, performance and power consumption.
The standard also builds on other standards such as the MIPI Alliance's M-PHY and UniPro specifications.
The UFS standard adopts the SCSI Architecture Model and command protocols supporting multiple commands with command queuing features and enabling a multi-thread programming paradigm.
In addition, a 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 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.
The basic initial data throughput supported is 300-Mbytes per second (MB/s), and the standard also supports command queuing features to raise random read/write speeds. JESD220 Universal Flash Storage may be downloaded free of charge from the JEDEC website http://www.jedec.org/standards-documents/results/jesd220.
How does this standard benefit the mobile device manufacturers when the standard is not mandatory to follow? Why did it take so long for JEDEC to come out with this standard, when the usage of flash in mobile devices has started long back?
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