Toshiba working on boosting SSD write speeds to 4.2Gbps

Using a boost converter

WITH THE INTRODUCTION of SATA 6Gbp, SSD drives got a much needed, faster interface, but it appears that we’ve hit another “wall” when it comes to performance of SSD drives, at least higher density drives. SSDs with more than 16 NAND Flash memory chips on them will have power issues in the near future which prevent them from reaching optimal write speeds. The good news is that Toshiba is already working to solve this problem with the help of a Japanese research group headed by Ken Takeuchi.

If we’ve grasped what’s being developed by the research group, we’re looking at a key requirement for the next generation of high capacity SSD drives. The story was originally reported by Tech-On, although some of the technical details as to what is actually being developed are a little bit unclear. There are a lot of mentions of a “boost converter” in the article and it sounds more like a car part than something that belongs inside an SSD. The boost converter is what makes the magic in this case, but it’s a little bit more complicated than that.

Most SSDs use what is known as a 3D layout of the NAND Flash. This means that several layers of Flash memory are stacked inside each physical chip, alongside things like a controller and power regulation circuitry to mention a few things. The issue is that in a typical SSD design, the power to each of the 3D NAND Flash chips are provided by a single power rail. If you exceed 16 NAND Flash chips you run into problems when you try to write data to all of the chips (or channels as they’re also known as) at once.

This is done when large amounts of data is being stored, something that isn’t unusual in typical SSD applications. The boost converter solves this by being fitted to each of the 3D NAND Flash chips, as it works in a similar way as a capacitor, by being able to boost the power to the NAND Flash. The new converter allows the supply voltage to be lowered to 1.8v instead of the usual 3v, so the flash chips using it consume less power overall.

The end result is that up to 24 channel SSDs are possible with the added advantage of a write speed performance increase of up to 4.2Gbps, compared to 2.6Gbps which appears to be the current limit. Another benefit of this new design is that the SSD can operate in an energy saving mode during regular read and write operations which will allow for a 68 percent reduction in power usage. It’s unlikely that we’ll see this implemented in SSDs this year, but at least it looks like the performance of SSDs will continue to increase and the hurdles on the way will be solved, one way or another.S|A

The following two tabs change content below.