So let us explain below all the details about this new type of external memory cards.
What about SD Express cards?
Before talking about the new microSD Express cards, it should be noted that SD Association unveiled the larger version “SD Express” on June 26, 2018 as part of the SD 7.0 specification.But no one pays any attention to “SD Express” cards, so that they were not released to the consumer that year despite the association's promise that they are five times faster than current SD cards.
Now, however, with the disclosure of microSD Express, it seems we may finally get cards with amazing transfer speeds for the laptops, smartphones and digital cameras we use.
It is not clear why no one was interested in “SD Express” cards. Perhaps because most companies were waiting for the microSD version before seriously starting.
This is often why, since microSD Express cards were announced at a business conference, as well as new card readers, and software controllers covering both versions of SD Express.
In general, there are no cards available for purchase by the consumer, at least not yet; but that should change in the not too distant future.
What are the new microSD Express cards?
MicroSD Express cards are the smallest version of SD Express storage. They are new types of SD cards and their advantage is support for an unprecedented read speed of 985 Mbps.To realize the difference more seriously: If we take existing microSD cards as a comparison, their speed is not even up to 200 Mbps. Similar to SD Express, microSD Express cards use PCIe 3.1 and NVMe v1.3 to achieve this fast data transfer speed.
These are the same technologies that SSD M.2 disks use in computers. The difference is that the new Express cards use only one PCIe path, whereas NVMe M.2 discs typically use four.
The small size of microSD Express cards makes it more convenient for the current way we use SD cards in phones and laptops. The only exception is digital cameras that prefer SD Card and built-in flash cards.
What's really new about microSD Express?
So far the news looks so good, the technology has evolved to the point that a small storage card can store and transfer data at the same speed as hard drives - perhaps faster. But these are just numbers. What about reality?In 2019, manufacturers began to take action to issue SD 7.1 specifications. The SD Association can put all the new specifications you want into the next generation, but if companies don't turn them into real products, they are just ideas.
For example, PCIe 4.0 was announced in 2017 but it became a reality with new PC products released in 2019. By the way, the PCIe 5.0 specification will soon be announced.
SD Express cards are currently experiencing the same problem with the slow adoption of mobile phone, computer and digital camera manufacturers, including SD cards.
So why is there hope for microSD Express cards? For one reason, at Digital Computex 2019, Western Digital (which owns SanDisk) introduced the SanDisk microSD Express card. The company did not announce the date of issuance of the card and its price, but the fact of its existence is a promise.