Subject: Storage | February 8, 2018 - 08:04 AM | Tim Verry
Tagged: UFS, Samsung, eUFS, embedded, automotive, adas, 256GB
Samsung announced yesterday that it has begun mass production of 256 GB eUFS (Embedded Universal Flash Storage) flash storage for embedded automotive applications. Doubling the capacity of the 128GB eUFS flash it announced last fall, the new embedded flash conforms to the newer JEDEC eUFS 3.0 standard including the new temperature monitoring and thermal throttling safety features which Samsung reportedly had a hand in developing. The new embedded storage is aimed at smart vehicles for use in driver assistance features (ADAS), infotainment systems, and next-generation dashboards.
The new eUFS 3.0 compliant flash is notable for featuring increased temperature ranges of between -40°C and 105°C for both operational and idle/power saving modes which makes it much better suited for use in vehicles where temperature extremes can be reach both from extreme weather and engine heat. Samsung compares its eUFS flash with traditional eMMC 5.1 storage which has a temperature range of only -25°C to 85°C when in use and -40°C to 85°C when in power saving mode.
Samsung’s eUFS can hit sequential read speeds of up to 850 MB/s and random read performance of up to 45,000 IOPS. Samsung did not specify write performance numbers but based on its other eUFS flash sequential and random writes should be in the neighborhood of 250 MB/s and 40,000 IOPS respectively. According to Samsung in its press material for 512GB eUFS for smartphones, the 256GB eUFS for the automotive market is composed of 8 stacks of 48-layer 256Gb V-NAND and a controller all packaged together to hit the 256GB storage capacity. Samsung has included a temperature sensor in the flash along with the ability for the controller to notify the host AP (application processor) at any pre-set temperature thresholds to enable the AP to downclock to lower power and heat to acceptable levels. The temperature monitoring hardware is intended to help protect the heat sensitive NAND flash from extreme temperatures to improve data reliability and longevity. The eUFS flash also features a “data refresh” feature that improves long term performance by relocating older data to less-often used cells. Embedded Universal Flash Storage (eUFS) is interesting compared to eMMC for more than temperatures though as it uses a dual channel LVDS serial interface that allows it to operate in full duplex mode rather than the half duplex mode of eMMC with its x8 parallel interface. This means that eUFS can be read and written to simultaneously and with the addition of command queueing, the controller is able to efficiently execute and prioritize read/write operations and perform error correction without involving the host processor and software.
I am looking forward to the advancements in eUFS storage and its use in more performant mobile devices and vehicles, especially on the low end in tablets and notebooks where eMMC is currently popular.