iNAND Drives Toward Automotive Market

　　Western Digital is directing its iNAND embedded flash to the automotive market.

　　The company’s iNAND storage portfolio came with the SanDisk acquisition; the latter company has previously positioned it for the increasingly high demands of smartphones, such as professional-grade digital photography and 4K Ultra-HD video playback.

　　Under the Western Digital umbrella, the technology is seeing opportunities for it to meet the evolving demands of advanced driver-assistance systems (ADAS), infotainment and safety systems, and other data storage requirements of connected vehicles. Gartner is forecasting that by 2020 connected and autonomous car data traffic per vehicle may reach more than 280 petabytes per year, essentially making the connected car a data center on wheels.

　　The iNAND 7250A EFD is available in capacities up to 64 GB and is designed to work with diagnostic systems continuously processing analytics, vehicle-to-vehicle and vehicle-to-infrastructure systems that are constantly streaming, and infotainment and navigation systems that are becoming increasingly complex. What these systems all have in common is that they generate, receive, and process data.

　　In a telephone interview with EE Times, Western Digital’s VP of embedded and integrated solutions, Christopher Bergey, said that the iNAND journey to automotive goes back as far as SanDisk’s acquisition of M-Systems, which had a focus on the embedded market. Since then, development of the iNAND portfolio has been largely driven by mobile handsets. “It was the largest market at the time and still is today,” he said.

　　He said that there was some use of iNAND in automotive applications in its earlier days, but SanDisk wasn’t taking a bottom-up design approach for specific markets. In the past few years, there has been a more systems-level approach to satisfy the particular performance, reliability, and capacity requirements of specific market segments.

　　iNAND was heavily promoted at the World Mobile Congress in 2015, including the ability for NAND cells to be formatted as both TLC and SLC, with the SLC areas having much higher write speeds, thanks to the newly introduced SmartSLC technology. Some of the overprovisioned areas of the flash are formatted as SLC, and the logic in the controller and the firmware monitor the requests of the host. When the firmware detects that the host needs high performance, it enables the device to control whether data is written to the smart SLC or to the main array.

　　Bergey noted that mobile has quickly moved to adopt TLC NAND, a trend backed by research firm Counterpoint. One in two smartphones sold globally includes a TLC NAND flash memory solution, according to its February 2017 report, and the advancement in graphics processing technology, as well as integration of high-resolution cameras in the phones, have resulted in a deluge of high-quality user-generated content from sharper high-quality images to high-resolution HD to 4K videos.

　　Adding advanced specifications such as imaging has led to significant efforts from memory suppliers to offer higher-capacity and advanced NAND flash memory solutions that can address these cost constraints without any compromise on performance, endurance, or user-experience, noted the Counterpoint report, and the industry has moved from SLC (single-bit per cell) to 2-bit MLC (two bits per cell) and to higher-density TLC or 3-bit MLC (three bits per cell or triple-level-cell).

　　Bergey said that design improvements have been made at the system level for mobile devices, but there’s also been a lot of excitement around automotive because the amount of data being stored and processed is increasing, leading to more compute modules in vehicles. “The amount of data in these modules is increasing exponentially,” he said. Western Digital is also seeing opportunities for iNAND in the industrial and connected home markets, he said, and there is more of a focus on creating additional value for OEMs incorporating them into their products.

　　Bergey said that plenty has been learned from the smartphone market, both in terms of sheer numbers of devices and the changing workloads. Improvements have been made to core controller technology that allow for economies of scale, he said, and are being applied in the automotive environment. In some cases, Western Digital is providing automotive-grade flash, while some subsystems are less demanding so commercial flash will do.

　　Bergey conceded that, given the multiple subsystems in the modern vehicle, there will be multiple memory technologies in play, including NOR flash and SRAM, but with all of the electronics being put into cars, most devices have considerable storage requirements with cost-per-bit remaining a factor. “NAND is a sweet spot because of its cost and the reliability we can provide at a system level.”

　　Bob O’Donnell, president and chief analyst of TECHnalysis Research, said that flash capacity and reliability has found itself in a position where it can meet all of the relatively sudden and rapidly emerging application requirements of automotive, the extreme temperature ranges outlined in AEC-Q100 Grade 2 and AEC-Q100 Grade 3, and the ISO26262 design guidelines for nonvolatile memory-based products. “It’s a very demanding standard,” he said. “Cars last 10 to 15 years, so you have to have storage that lasts a long time.”

　　In a telephone interview with EE Times, he said that the estimates on how much data connected cars, particularly autonomous ones, will be sorting and processing, should not be underestimated. An autonomous vehicle generates four terabytes a day. O’Donnell said that increasingly higher-resolution maps and sensor data need to be accommodated. “It’s small now, but you are going to see a lot more of it.”

　　Automotive companies are looking several car seasons ahead, he added, so they have to start planning for these higher capacity solutions now.

　　O’Donnell does see parallels with the smartphones in terms of NAND flash adoption and expansion, but while the latest and greatest smartphones are hitting the 256-GB mark, automotive is rapidly outpacing it in terms of storage needs. “That local storage demand is going to continue to rise.” He said that connected homes are also a viable segment for flash such as Western Digital’s iNAND, although capacity-wise, it’s at the other end of the spectrum, as popular items such as the Amazon Echo are primarily thin clients. “That category is growing like crazy.”