In order for the SD 7.0/7.1 (aka SD Express) ecosystem to take off, a number of things are needed, but aside from specification itself, availability of controllers for card readers as well as controllers for cards is crucial. Apparently, Phison had already developed its first controller for SD Express and microSD cards and even showcased prototypes of such cards at Computex.

Phison’s PS5017 controller is compliant with the SD 7.1 specification, so it can be used both for SD Express and microSD Express cards. The chip supports various types of 3D TLC and 3D QLC NAND memory featuring ONFI or Toggle 2.0 interfaces, but total capacity is limited to 512 GB for some reason. Performance wise, the controller promises up to 900 MB/s sequential read speed as well as up to 500 MB/s sequential write speed, which is good enough considering types of memory that it will be used with.

Since the company has not formally announced the PS5017 controller, it is likely that is has not passed all of required compliance tests just yet. Meanwhile, since the company showcases prototypes of cards as well as mentions the chip publicly, it is likely that it is in its final stages of development.

While Phison does not announce any firm ETA dates for its PS5017, it looks like makers of SD Express and microSD Express cards will be able to buy it in the coming quarters.

Want to keep up to date with all of our Computex 2019 Coverage?
Follow AnandTech's breaking news here!
Comments Locked


View All Comments

  • deil - Monday, June 17, 2019 - link

    on read not write & 256 GB cards. And most people use 64 GB/32GB ones....
  • damianrobertjones - Monday, June 17, 2019 - link

    Does this mean that sales of sd cards have finally fallen? If so this could be why they're now planning on improving them to keep the $$$$ moving.
  • desolation0 - Tuesday, June 18, 2019 - link

    Phone and other portable device sales have been tailing off almost across the board. That likely suppresses one of the demand drivers for micro sd card sales. Having new tech like SD Express would give an additional point to upgrading the previous gen handset for a time. Having this in new cameras obviously helps there as well.
  • Xajel - Monday, June 17, 2019 - link

    I'm only wondering as the SD Express spec was already this late, why they didn't add support for PCIe 4.0 already? I mean they still need more time to actually have the cards/controllers not to mention the actual products, and PCIe 4.0 is just ringing the bell now. Soon it will find it's way for more products, the only reason I see they went for PCIe 3.0 instead is that PCIe 4.0 support could delay the actual products even more.

    PCIe 4.0 will double the bandwidth, seeing the SD Express is limited to x1 lanes only, PCIe 4.0 support should bring us closer to 2GB/s. While some will say this is beyond our current needs, true, but considering that SD cards will be able to reach over 1TB soon then 2GB/s speed is good to actually read the full card quickly after being used.
  • LordanSS - Monday, June 17, 2019 - link

    I'd say power restrictions would be one of the reasons (at this point in time).
  • carcakes - Wednesday, August 14, 2019 - link

    Yes, pci-e 4.0 could double the speed on sd express and nvme 1.4 instead. They could have gone to pci -e 5.0 and then quadrupled it. It sounds like an idea for a dual gpu card like radron SSG AGAIN.
  • carcakes - Wednesday, August 14, 2019 - link

    Radeon SSG GPU
  • carcakes - Wednesday, August 14, 2019 - link

    There is also only SD 7.1 standard. Maybe when SD 8.0 is out it will

Log in

Don't have an account? Sign up now