SD Express enables 128TB cards with 985MB/s

The SD Association published a whitepaper that details the specifications of SD7.0.

Among other things, the new spec enables SDUC (SD Ultra Capacity) memory cards with a maximum capacity of 128TB, although it will probably take a very long time until we actually see something that approaches this limit. The current SDXC spec allows for cards of up to 2TB, but those don't exist yet.

Next we'll also get SD Express memory cards that take advantage of the PCI Express 3.0 and the NVMe 1.3 protocols, these cards will enable theoretical speeds of up to 985MB/s, up from the 624MB/s allowed by the current standard. SD Express can also serve as removable solid state drives (SSDs).

SD Express will offer backwards compatibility, you will be able to use old cards in SD Express hardware, and SD Express cards will function in old hardware at reduced speed.

With SD memory cards used for higher capacity as well as speed intensive applications and massive storage for devices of all types, there is a growing need for a big jump in random and sequential performance levels as well as more modern protocols. The SD Express feature introduced in SD7.0 includes the added PCIe and NVMe interfaces enabling new opportunities for SD memory cards and opens a whole new world of uses while keeping backward compatibility to billions of existing SD host. The SDA made adoption easier thanks to allowing existing knowledge by using given building blocks and available test equipment.