Memory Roundup: Resistive RAM for AI, Upcoming DDR5 Specifications, and the Latest on 3D NAND

June 06, 2018 by Chantelle Dubois

Today’s roundup touches on how resistive RAM could change artificial intelligence applications, what to expect with upcoming DDR5 RAM specifications, and the latest news on 3D NAND flash memory.

Today’s roundup touches on how resistive RAM could change artificial intelligence applications, what to expect with upcoming DDR5 RAM specifications, and the latest news on 3D NAND flash memory.

Memory plays a vital role in the hardware domain—availability, cost, efficiency, and speed significantly influence design. What's trending right now in the memory niche? Let's take a look at recent announcements and innovations in ReRAM, DDR5 RAM, and 3D NAND flash memory.

Resistive RAM for Edge Computing

Crossbar recently announced a partnership with Microsemi to eventually include Resistive RAM (ReRAM) on future chip designs and has made licensing of the technology available. Crossbar seems to be anticipating that ReRAM will play an important role in future applications of artificial intelligence, bringing AI neural networks onto embedded systems instead of in the cloud. This could make an impact on everything from autonomous driving to IoT where there is already a trend of processing moving to the edge of networks. 

What makes ReRAM different is that it is a non-volatile memory that operates by changing the resistance of memristor materials. It’s faster than MRAM and PRAM due to material properties, has a simple structure, has low access latency, fast writing performance, high density, and requires less energy.


Crossbar's visual aid of their stackable ReRAM structure

Crossbar's visual aid of their stackable ReRAM structure. Image courtesy of Crossbar.


Several companies have been working on ReRAM over the past decade or so, including Panasonic, HP, Adesto Technologies, and (of course) Crossbar. Panasonic is the only company so far to commercially make ReRAM available with the MN101L ReRAM embedded 8-bit MCU.

ReRAM may have the potential to eventually replace flash memory, especially if costs become comparable and if flash memory shortages continue to plague the industry.

DDR5 Specifications Expected Soon

Specifications for the next generation of Double Data Rate memory, DDR5, are expected to be released sometime in the next few months. What is known about DDR5 so far is that it will be twice as fast as DDR4, and twice as power efficient, following the existing DDR trend.  

Also expected is 1.1V supply (versus 1.2V in DDR4) and data rates of 6.4Gbps. Once the specifications are released, it is expected that the first products may begin using DDR5 sometime in 2019 or 2020, and are anticipated to overtake DDR4 in usage by 2022. 


DDR5 devices mounted on Cadence's test board

DDR5 devices mounted on Cadence's test board. Screenshot courtesy of Cadence.


That timeline may seem long, but work on DDR4 began in 2005, details released in 2008, standards released in 2012, and first products with DDR4 available in 2014. 

Cadence demonstrated a DDR5 IP prototype earlier this year, showing 37.5% improvement in speed over DDR4. 

More 3D NAND News in 2018

Since the 2D NAND flash memory shortage that began in 2016, 3D NAND has been seen as one of the most viable alternatives—but initial challenges with manufacturing have made the adoption slow since 3D NAND stacks memory cells on top of one another and requires relatively precise alignment.


Memory Technology Roadmap

Image courtesy of Western Digital.


However, so far in 2018, there have been more companies stepping up to begin production. Toshiba Memory Corp. announced they will begin constructing facilities where 3D NAND will be fabricated beginning this upcoming July, and will be completed in 2019. 

Western Digital, on the other hand, has begun shipping 96-layer 3D NAND memory to retail customers, while Adata announced industrial 3D NAND SSDs for data centers.

Unfortunately, it may still be a while before 3D NAND devices are available for regular consumers. 



Got other memory stories and news you want to learn more about? Let us know what you're curious about in the comments below.