Toshiba Begins to Sample eMLC-Based ZD6300 7.68 TB SSDs to Customers

Toshiba has quietly expanded its ZD6300 family of SSDs with a 7.68 TB model, its most capacious storage device announced to date. The new drive was designed for mixed workloads and uses Toshiba’s time-proven A19 eMLC NAND flash memory. Due to enhanced endurance and a lot of NAND used for overprovisioning, the SSD can be pre-ordered for approximately $12,000, depending on the seller, though its official MSRP is still unknown.

The Toshiba ZD6300 7.68 TB (ZD635E020-7.68T) SSD uses PMC-Sierra’s “Princeton” controller (which is now called Flashtec NVMe PM8604 1032) with PCIe 3.0 x8 interface (which Toshiba splits into two x4 interfaces), 16 NAND flash channels and NVMe 1.1b protocol. The drive will be available in 2.5”/15 mm form-factor with U.2 connector (SFF-8639) in a bid to enable compatibility with different server chassis (specifically for those, which support multiple SSDs). The new 7.68 TB drive from Toshiba support the same functionality as other ZD-series drives from the company (which were originally introduced under OCZ brand), such as dual-port capability, AES-256 encryption, full power loss protection, end-to-end data protection and so on.

The ZD6300 7.68 TB SSD uses higher durability eMLC memory to guarantee better endurance, which is why it supports maximum sequential write speed of up to 2.9 GB/s (in line with the ZD6000-series drives). However its maximum sequential write speed is 1.4 GB/s (or actually lower) due to higher program latencies of eMLC (which is in line with other ZD6300-series products).

Typically, the key differences between the ZD6000 and the ZD6300 SSDs (which were officially announced) were usage of eMLC by the latter in order to enable three drive writes per day (DWPD) over a five-year period, which was more suitable for mixed workloads (something that the ZD6300 were designed for). What is important is that the Toshiba ZD6300 7.68 TB SSD belongs to the less-known Max Capacity sub-family from the Z-Drive 6300 product stack that uses eMLC, but not in order to enable 3 DWPDs, but to maximize capacity using more durable ICs. The ZD6300 Max Capacity family has not been announced officially, but such SSDs are available for purchase (as pointed out by Ilya Gavrichenkov, my former colleague from another web-site). The ZD6300 Max Capacity drives do not reserve vast amounts of eMLC NAND flash for overprovisioning, unlike the regular ZD6300-series products, to enhance endurance, but this allows it to increase capacities by 20%, albeit at a relatively high per-gigabyte cost.

Consequently, from a raw NAND capacity configuration point of view, Toshiba’s ZD6300 7.68 TB SSD is the same drive as the ZD6300 6.4 TB product: it has 8128 GB of memory, but it makes 7680 GB available to the user rather than 6400 GB. Just like the ZD6300 6.4 TB drives, the 7.68 TB model uses 32 of 16-die packages featuring 128 Gb eMLC NAND flash memory devices produced using Toshiba’s second-generation 19 nm process technology.

It should be noted that apart from the ZD6000/ZD6300 SSDs with one or three DWPD, Toshiba also offers high-endurance SSDs with 10 or 25 DWPDs in their ZD-series product lineup. Such drives are naturally more expensive, but those, who need very high endurance, are usually willing to invest in such storage solutions. Still, since requirements of such customers are very diverse, Toshiba does not publish specs of such drives because virtually all of them are built to order and are not available from usual resellers.

Speaking of availability, Toshiba tells us that it is sampling the ZD6300 7.68 TB product with customers. Meanwhile, there are several resellers, who are offering to pre-order the SSD for $12,563, $12,090 or even $11,252. Since the product is still in the sampling stage and is not yet officially shipping, Toshiba naturally keeps its actual price under wraps.

Western Digital to Use 3D ReRAM as Storage Class Memory for Special-Purpose SSDs

At the Flash Memory Summit this week, Western Digital announced that it intends to use 3D Resistive RAM (ReRAM) as storage class memory (SCM) for its future special-purpose ultra-fast SSDs. The company did not reveal any actual timelines for appropria…

Maxiotek Unveils MK8115: Low-Cost SSD Controller for 3D NAND SATA SSDs

Maxiotek this week introduced its first SSD controller designed for affordable SSDs with an SATA interface, which is meant to be paired with new types of NAND flash memory, including chips with 3D architecture as well as ICs made using thin fabrication processes. The company is working with various makers of SSDs as well as OEMs, so actual drives based on the MK8115 will hit the market in the foreseeable future. In fact, one of the first drives featuring the chip is ADATA’s SU700, which was demonstrated back at Computex.

The Maxiotek MK8115 is a quad-channel controller that supports a SATA 3.2 host interface as well as various types of SLC, MLC, 3D MLC, and 3D TLC NAND flash memory. Internally, Async, Toggle, and ONFi NAND interfaces are supported, with up to 400 MT/s transfer rates. The MK8115 controller supports the developer’s AgileECC error correction (with programmable ECC parity that supports 1 KB code-word length correctable up to 76 bits, something that implies on BCH method) with virtual parity recovery; modern security capabilities like AES-256, SM4, TCG-OPAL 2.0, IEEE1667; low-power modes (Slumber/Device Sleep, etc.); advanced static/dynamic wear-leveling and so on. One of the key features that Maxiotek advertises about its MK8115 is the fact that it does not require DRAM, thus allowing to build very affordable SSDs.

When it comes to compatibility with actual memory, the MK8115 supports SLC NAND produced using 20 nm-class fabrication processes, MLC NAND made using all three iterations of 10 nm-class manufacturing technologies (1x, 1y, 1z) as well as IMFT’s 3D MLC and 3D TLC NAND flash. The controller can support up to 1536 GB of memory (when coupled with IMFT’s 384 Gb 3D TLC ICs), which should be enough for low-cost SATA SSDs for at least a couple of years.

Performance-wise, the MK8115 is on par with other SATA 3.2 devices: it can handle up to 560 MB/s sequential read speed and up to 530 MB/s sequential write speed. As for random operations, the new SSD controller is rated to perform up to 100K random read IOPS as well as up to 75K random write IOPS. In a bid to boost writing performance of 3D TLC NAND-based SSDs, the MK8115 can also use a part of the NAND in pseudo-SLC mode, which is what other controllers do these days as well. Maxiotek claims that the upcoming DRAM-less SSDs powered by the MK8115 will perform just like drives featuring DRAM cache (to store LBA tables) in typical workloads.

The Maxiotek MK8115 chip is available in 12×12 mm² 288-ball TFBGA package and use 3.3V/1.8V/1.2V power supply, which make it compatible with SSDs in M.2 and mSATA. Since SATA 2.5” form-factors require +5V and +12V rails, to build such SSDs featuring the MK8115, manufacturers will have to integrate a basic VRM into the package, which should not be too hard.

Maxiotek may not be a household name, but the company is basically a spin-off from JMicron, whom focuses solely on SSD controllers. The two companies are still based in the same building in Hsin-Chu, Taiwan, but we have no idea whether they share any resources. Nonetheless, a good news is that Maxiotek will not start to build itself from scratch, but will continue from where JMicron stopped. At least, the company says it has an experienced team of engineers as well as relations with partners, which include all major makers of SSDs as well as PC OEMs.