SD Association adds the new SD Express which utilizes the PCI-express and NVMe interfaces to delivering blistering transfer speeds up to 985MB/s between SD host devices and memory cards. The new SD Express also uses the SD memory card form factor and it benefits from NVMe’s upper layer protocol advanced memory access mechanism. With SD Express, SD memory card capacity is also increased with capacity ranging from 2TB with SDXC to a massive 128TB with the new SD Ultra Capacity (SDUC) card. SD Association also confirms backward compatibility with the SD Express and also releasing the new SD 7.0 specification.



The new SD Express uses the PCIe 3.0 specification and NVMe v1.3 protocols as defined by PCI-SIG and NVM Express on the second row of pins used by UHS-II flash cards today. The upcoming SD Express cards will be able to provide system developers new options offered by PCIe and NVMe capabilities, such as Bus Mastering, Multi-Queue (without locking mechanism) and Host Memory Buffer.

Host Device Matching

Any speed cards can be used in UHS-I, UHS-II, UHS-III and SD Express host devices. Faster performance levels will only be attained when matching the card to the host device. Therefore, devices supporting UHS-I perform best with UHS-I memory cards. UHS-II cards should be used in devices supporting UHS-II. UHS-III devices should use UHS-III cards. SD Express devices will perform best when using SD Express cards.

Learn more about the new SD Express Bus interface at the SD Association website.