SSD power fail protection is essential to retain critical data in the event of a power failure. The power fail protection challenge is more significant in MLC designs than SLC because of a phenomenon known as “paired page writes.” When an SSD writes to MLC NAND flash, there are two blocks open at the same time. The data in those blocks is subject to corruption if the power goes out during a write. SLC does not use paired pages and therefore does not incur this challenge.
Some SLC SSD manufacturers think that a hardware solution is enough. When they transition to building MLC drives, they run into problems. Also, some manufactures go for raw speed, so they take shortcuts by acknowledging to the host system that they “have the data” when it hasn’t been committed to the flash. If power goes out during this time, data is lost, operating systems get scrambled and there are failures.
In the industrial embedded market where Virtium focuses, our vtGuard power fail protection solution is a key feature integrated into the hardware and firmware of both of our SLC and MLC designs. We build in a dedicated power protection circuit at a nominal added cost. But the result is rock-solid, robust SSD that provides a better match for our industrial embedded market. This added protection is money well spent, in terms of total cost of ownership and data security – something consumer-grade SSDs can’t offer.