SD Association (SDA) announced new SD 9.1 specification, doubling the SD Express memory cards speed (up to 2GB/s) and new SD Express Speed Classes:
"The latest generation of microSD Express uses the PCIe interface delivering a 1,969 megabytes per second (MB/s), nearly 2 gigabytes per second (GB/s) speeds by using the PCIe Gen4 x1 lane as defined in the latest update to the microSD Addendum version 8 specification. microSD Express was introduced with 985 MB/s speed maximum data transfer rate and the NVMe upper layer protocol in the SD 7.1 specification. The increase in speed gives product designers more storage options and SSD level performance for a variety of size constrained devices requiring easily repairable or upgradeable storage.
The SD Express Speed Classes are used exclusively on SDXC, SDUC, microSDXC and microSDUC memory cards offering the SD Express bus. Changes in memory technology necessitate the need to define speeds as NAND flash technology continues to evolve. SD Express is the most significant evolution for SD since it was introduced in 2000. It meets new and evolving market needs to support increased performance requirements of controllers, memories, and other application interfaces. SD Express can fully support almost every use case demanding higher speed removable or semi-removable memory cards and is ideal for meeting the growing number of Right to Repair laws."
