Transcend offers one of the broadest ranges of SSDs and flash memory cards, with products for almost every form factor and even some legacy interfaces like IDE. Part of the variety comes from products intended for industrial use, with features such as extended temperature ratings or the use of SLC NAND for improved write endurance and performance.  However, trends in flash memory technology and the SSD market over the past few years have led to SLC products all but disappearing from the market as MLC-based SSDs have demonstrated sufficient performance and durability for even the most demanding enterprise customers. Many of Transcend's SLC-based products have now been outclassed by their MLC-based counterparts using newer controllers and reaping the performance benefits of higher capacities and more flash chips.

For these reasons, Transcend has announced that their next generation of industrial-grade SSDs will be taking a new approach to providing high durability. What they are calling SuperMLC will consist of premium-binned MLC flash memory that is operated as SLC flash, with only one bit stored in each flash cell instead of two. We've seen this sort of pseudo-SLC operating mode used by many TLC-based SSDs and a few MLC drives to provide a small but fast write cache, but we haven't previously seen this used for an entire drive.

For the cost of halving usable capacity relative to normal two bit per cell MLC, Transcend claims their SuperMLC can provide four times the sequential write speed and an effective Program/Erase Cycle rating of 30,000. Flash manufacturers are increasingly reluctant to disclose specifics of durability, but based on whole-drive endurance ratings and wear indicators we've been able to estimate that even the 3D NAND used in Samsung's 850 Pro consumer MLC drive is only warranted for 6,000 P/E cycles, and most recent planar NAND MLC is rated for around 3,000 P/E cycles. Selective binning often means that enterprise drives have higher durability, but using the flash as SLC is guaranteed to add even more to its endurance.

By starting with the same MLC flash memory used in mainstream SSDs instead of the niche product that is SLC NAND, it's likely that Transcend will be able to cut costs significantly as they're buying from a market with much greater supply and MLC dies that don't make the cut for their SuperMLC products can still be sold in their consumer-grade products.

Transcend plans to introduce SuperMLC drives over the course of 2016. The products announced so far are SSD510K (2.5" SATA), MSA510 (mSATA), HSD510 (half-slim form factor; essentially a 2.5" drive PCB that's only half as long as a 2.5" drive case), and MTS460 and MTS860 will be two sizes of M.2 (presumably also using a SATA interface rather than PCIe).

Source: Transcend

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  • FunBunny2 - Thursday, December 31, 2015 - link

    -- By starting with the same MLC flash memory used in mainstream SSDs instead of the niche product that is SLC NAND

    some background on this statement? last I knew, all NAND (on a given node, etc.) was the same, SLC/MLC/TLC being a figment of the controller's imagination.
  • menting - Thursday, December 31, 2015 - link

    no..that's not true. SLC/MLC/TLC are definitely different as far as chip layout goes.
  • woggs - Thursday, December 31, 2015 - link

    Can be either way. This is completely up to the manufacturer on a case by case basis. It's cheaper to design and build one piece of silicon, so that's the starting point and there needs to be technically compelling reasons to make custom silicon for the SLC and MLC parts.
  • Blazorthon - Sunday, January 3, 2016 - link

    SLC, MLC, and TLC are all different in hardware, not merely software. The controller can take MLC and TLC and treat them similarly to SLC by ignoring the second bit in MLC and both the second and third bit in TLC for each cell. This is not a perfect replacement for SLC, but it means that Transcend can buy standard MLC NAND chips instead of getting SLC chips custom-made.

    This is better for performance and reliability granted at the cost of half the capacity, because it is easier to write to the first level of a NAND memory cell than the second or third levels. With TLC, writing to the third level is so difficult that it's avoided when at all possible and TLC needs very powerful error correction for when writing to that third cell is necessary to at least somewhat ensure data integrity.
  • woggs - Thursday, December 31, 2015 - link

    The difference is the manufacturer choosing to configure, qualify and sell a specific SLC device or not, which can be the same physical piece of silicon with special configuration or might be a different silicon design altogether. In this case, transcend is making the choice to either use the "SLC mode" of the MLC part or skip to addresses that make up the 2nd bit of the flash cell and leave only the first bit programmed. In theory, that first bit programmed has higher reliability if left that way.
  • Byte - Sunday, January 3, 2016 - link

    MLC and TLC were created to increase density as there was diminishing returns when shrinking the die process for flash memory. After sufficient generations, it is now cheap enough to waste 1/2 or even 2/3 of the usable memory to gain speed. SLC costs too much to pump out, while MLC and TLC are flooding the market, so being able to use these commodities for double duty will be great.

    This should work out well to reinvigorate the stagnant sector as people are willing to pay double for an 850Pro and triple for a 950Pro. Maybe samsung will finally have some competition in the high end sector.
  • Samus - Thursday, December 31, 2015 - link

    I have a hard time justifying Transcend and "Industrial" in the same sentence.
  • smilingcrow - Thursday, December 31, 2015 - link

    Open your mind and transcend its limitations.
  • extide - Thursday, December 31, 2015 - link

    Sounds like a personal problem to me, they are used in a LOT of stuff!
  • Samus - Saturday, January 2, 2016 - link

    Well, you're right, I am basing my bias on experience, and it is in regards to their consumer-class products, specifically flash drives and consumer SSD's. I've had a 16GB flash drive fail and seen an SSD lock itself (Sandforce 2281-based SSD370) and no longer detect in BIOS, but both could have been localized incidences. But that's in stark contrast to Sandisk, Crucial/Micron/Lexar products where I've never seen a failure.

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