On May 19, 2020, the SD Association announced the SD 8.0 standard for SD Express cards. As usual, everything new is better, faster, with PCIe 4.0 and supports backward compatibility. Let's figure out what awaits us in this fairly popular form of memory cards in the near (or, as usual, not so near) time.
There could be a long description of where the SD cards are found, but you probably already know that.
Let's get started!
Table of contents
01. Short information
02. A bit about SD and PCIe / NVMe
03. The need for a protocol that provides high speed
04. Advantages of SD Express with PCIe / NVMe
04.1. Differential Interface
04.2. Encoding 128b / 130b
04.3. Energy Efficiency
05. Useful Links
06. Conclusion
So, what you need to know about SD Express at the moment:
- All SD Express will be backward compatible;
- SD Express theoretically allows a bandwidth of 3,938 MB / s (2 PCIe 4.0 lanes, currently only full-sized SD with 27 pins);
- microSD with PCIe 4.0 is not yet supported;
- SD Express connected via PCIe will be recognized by the host as standard NVMe devices.
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02. SD PCIe/NVMe
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04. SD Express PCIe/NVMe
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04.2. 128b/130b
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04.3.
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