What’s the Latest on Universal Flash Storage?

Recently, at DesignCon 2014, I had the pleasure of moderating a panel on universal flash storage (UFS). This was my second year with the panel, and I was glad to be back to get an update on where UFS is, what challenges remain, and what the future holds.

There is no doubt that the mobile communications market has moved well beyond voice. I know this to be true even when I watch my father-in-law, flanked by my two teenage daughters, who are conscientiously explaining to him the advantages/disadvantages of an iPad vs an iPad mini, each demonstrating on her own tablet. They are telling him he doesn’t need to bother to get a new computer; he just needs a tablet. And, he’s buying it.

Plus, the regular news of wearable devices and a connected world leave me in no doubt as to the importance of finding low-power, high-performance mobile solutions for just about anything. Fortunately, JEDEC has developed an embedded mass storage approach known as universal flash storage (UFS).

The first speaker on the DesignCon panel was Kathy Choe Thomas, who was also a panelist last year. She is senior product marketing manager, NAND flash products, for Samsung Semiconductor. In addition, she serves on the Universal Flash Storage Association (UFSA) board of directors and as chairman of UFSA Marketing Committee. She put UFS in context with what she termed the “mobile computing revolution.” Choe Thomas pointed out that while 80% of the world’s population have mobile phones, only about a quarter of the world’s population have smartphones.

She shared another statistic: in the fourth quarter of 2012, tablet shipments surpassed PCs/notebooks combined. This was less than three years after tablets were introduced. The smarter, faster, and more powerful mobile devices being designed now require smarter, faster, and more powerful memory. The key mobile memory requirements are low power and fast performance.

Thomas also talked about the evolution of mobile memory, mentioning the JEDEC-defined storage solutions optimized for mobile devices. eMMC is open mobile storage with low power. It is mature, but not scalable. UFS, on the other hand, is scalable, and offers higher performance while maintaining low power. In terms of “What is UFS?” she explained it as a tiny SSD for mobile. Some statistics:

  • UFS 2.0 exceeds current SSD interface of SATA 3.0 (6 Gbit/s). Supports up to Gear 3 at 600 Mbit/s per lane with multi-lane support.
  • UFS supports multiple interface speeds. Host can adjust interface based on its needs in real-time.
  • High-speed serial interface, future expandability/scalability built-in, multi-lane support
  • Asynchronous I/O, command queuing and reordering

Next, John Geldman, director, industry standards, Micron Technology, took on the question: What exactly is “SSD for Mobile?” He pointed out that UFS supports one or two “lanes” (for 2x bandwidth) and it supports performance ranges from 125 Mbit/s (one lane of HS-G1) to 1.2 Gbit/s (two lanes of HS-G3). He also detailed the UFS command sequence and what UFS can do to minimize interface power. Geldman noted that the initial form factor for UFS is BGA, with a microcard under discussion.

Zachi Friedman is director of product marketing, mobile storage, at Arasan Chip Systems where he is responsible for all mobile storage IP products. His NAND Flash experience spans devices, controllers, and SSDs. He has worked in networking, InfiniBand, and Ethernet. He talked the group through how to create a UFS implementation and fielded questions on IP. He discussed the UFS layered architecture and how to validate a UFS design.

Next up was another veteran panel member, Perry Keller, who is the application and standards program lead at Agilent Technologies. He serves on the JEDEC and UFSA Boards of Directors and is Chairman of JEDEC’s UFS Measurement Subcommittee and UFSA Compliance Committee. Keller talked about the “UFS ecosystem,” explaining what will be involved in getting UFS into the mainstream, including the efforts of JEDEC, UFSA, the MIPI Alliance, and others. He detailed the UFS compliance test process.

Overall, this was another great panel on UFS for DesignCon. There seemed to be much more informed questions from a larger audience this year, as UFS has advanced a great deal in the last year. Any questions on UFS? Let me know in the comments below.

This story originally appeared on our sister site, EDN.

— Janine Love Circle me on Google+ Follow me on TwitterVisit my LinkedIn page, UBM Tech