"FRAM can offer almost unlimited endurance," says senior director
TORONTO — Does ever-emerging Ferroelectric Random Access Memory(FRAM) have a role in autonomous vehicles? Cypress Semiconductor thinks so.
At the Embedded World trade show in Germany this week, the company unveiled a new serial nonvolatile memory family to meet the performance and reliability demands of mission-critical data capture. In an advance telephone briefing with EE Times, Sonal Chandrasekharan, senior director of Cypress’ RAM Business Unit, said that the Excelon (FRAM) line was designed specifically for the high-speed nonvolatile data logging needed for autonomous vehicles. More broadly, the new FRAM line has applications in a broad range of advanced automotive and industrial applications.
The Excelon Auto series offers 2-Mb to 4-Mb automotive-grade densities, while the Excelon Ultra series offers 4-Mb to 8-Mb industrial-grade densities. Both families are available in low-pin-count, small-package options. The Excelon Auto series is offered in AEC-Q100 extended temperature options with functional safety (ISO 26262) compliance. “It’s the first functional safety-compliant NVRAM in the market,” said Chandrasekharan. “It’s focused really on the safety requirements within the automotive market.”
She said that both Excelon Auto and Ultra are meant for use in transaction logging in automated systems. It’s not a new application. On a factory floor, for example, a robotic arm needs memory that stores its movements in case of a power failure so that it can start again from the exact same point. “On older-generation devices, you used to do that with a static RAM and backed it up with a battery. The battery itself was the most unreliable part of the system. That’s where the need for the non-volatile RAM came up.”
FRAM can offer almost unlimited endurance, added Chandrasekharan. “It is practically an SRAM because you’ll never wear out the cell.” It also writes at very low power, and its data retention is superior to all other technologies. Chandrasekharan said that with the explosion of Internet of Things (IoT) devices, Cypress expects that by 2020, nearly 70% of the market will be industrial IoT and require data-logging capabilities.
Industry 4.0 is driving Cypress’ growth in industrial systems, where it plays in the two middle stacks, either the shop floor in the plants and the end-to-end or machine-to-machine communication change that’s going to happen, said Chandrasekharan. “The multiple devices at the field level will control what happens in the factories and the shop floor. Whether these are sensors or actuators or small machines, they send control signals that operate what’s happening at the automated machines in the factory.”
Cypress is one of very few companies currently exploring applications for FRAM, said Jim Handy, principal analyst at Objective Analysis. Since acquiring Ramtron, the company has been infusing funds to make FRAM technology more commercially successful. Its use in event loggers for automakers is not dissimilar to efforts in the 1970s to build driverless control systems for the San Francisco BART trains. The idea was that no one could point fingers at someone else if there was an accident because the trains were autonomous and all relevant data was captured.
From a technology standpoint, event logging is something that FRAM is well-suited for. “Whether autonomous vehicles are adopted quickly or not, there is still a push for event data recorders,” said Handy. “It looks like a really good application for FRAM,” despite the fact that it doesn’t scale very well. “You don’t need a large memory; you just need to record 10 seconds before the car rolls over. You could be constantly overwriting it until something happens.”
The fast write speeds also make FRAM attractive for industrial and medical applications, said Handy. For the latter, its radiation tolerance is appealing, too. Other uses include reloadable fare cards for public transit systems, as they don’t need large capacity. It doesn’t appear as though Cypress is looking to do aggressive scaling, he said. Instead, it’s looking at the problems that customers are willing to spend money to solve with fast writes and non-volatility. “It limits the market size significantly, but it could still be a very profitable niche.”
—Gary Hilson is a general contributing editor with a focus on memory and flash technologies for EE Times.