Silicon Motion Introduces SM2708 Controller: 1700MB / s SD Cards

Memory cards will not be left behind thanks to the SD Express standard, which will feature the first SM2708 controller to use PCIe 3.0 x2. Speeds are expected to be around 1700 MB / s read, maximum.

It seems that SD cards will not be extinguished, but their performance will be improved to sky-high levels. Until now, we had the Phison PS5017 controller, but Silicon Motion presents its SM2708: it uses 2 PCIe 3.0 lanes. In fact, memory cards make use of PCI-Express 4.0 in the future to reach 3940 MB / s is planned.

Silicon Motion SM2708, the future of SD cards is here

The SD Express and PCIe interface 3.0 is the first stage of the performance increase in writing speed in this medium. The news focuses on the introduction of the SM2708 controller that supports the SD 7.0, 7.1 and 8.0 specifications (UHS-I SD 6.1 and PCI-Express, using the NVMe protocol ).

It is characterized as using 2 PCIe 3.0 channels to achieve a gross data rate of 1969 MB / s. Until now, Phison had introduced the PS5017, a controller that was compliant with the SD 7.0 specification and used only one lane of PCIe 3.0 to achieve 870MB / s maximum.

This new controller supports the UHS-I interface, as well as 3D NAND memories since Silicon Motion owns the ECC NANDXtend technology. So the built-in NAND Flash interface makes it support up to 1200 MT / s.

In fact, using PCIe 3.0 x1, the SM2708 controller could go up to 900MB / s, which is already more than Phison has achieved. Of course, the SD Express memory cards do not seem to be arriving soon because they do not appear on the market.

Then? For now, it is estimated that SD Express cards will be used in drones, high-resolution cameras, etc., media that will not be available to the mainstream, nor will they be viable as a product for consumers.

However, Silicon Motion is not only introducing the SM2708 controller, but a complete kit made up of firmware for third-party vendors who want to use it on their SD Express cards.

Although they have not yet reached the market, the SD Association has a job on the table: getting out cards that use PCIe 4.0 x2. Within the world of storage, only PCIe 4.0 SSDs are the only ones to use this interface (or x4), reaching 7000 MB / s of writing. In the case of memory cards, 3940 MB / s would be achieved using PCIe 4 × 2.

Finally, note that the control unit is compatible with the NVMe 1.3 protocol, the PCI Express 3.1 interface and that it supports L.1.2 (energy saving mode that allows it to consume less than 1.5 mW). Also, it supports the NAND ONFI 4.1 and Toggle 3.0 interfaces.