Like many other sectors, the automotive industry is adopting 5G technology to achieve high-speed, low-latency connectivity. Vehicle communication systems, however, can only support these faster data rates with high-performance memory subsystems.

Kioxia's new UFS 4.0 Flash devices.

Kioxia recently announced that it is now sampling the industry’s first Universal Flash Storage (UFS) 4.0 embedded flash memory device designed for automotive applications.

Devices Built on BiCS Flash

At the core of these UFS 4.0 devices is Kioxia's BiCS 3D Flash memory technology. BiCS Flash moves away from the traditional planar structures to a more advanced 3D stacking process. First announced in 2007, this technology has evolved from 48 layers in 2015 to an impressive 162 layers by 2022. This enables higher-density storage solutions without the proportional increase in cost typically associated with additional memory layers.

Kioxia’s UFS 4.0 is based on its BiCS Flash technology.

Kioxia's new UFS 4.0 devices integrate this 3D Flash memory with a controller in a standard Jedec package, supporting interface speeds up to 23.2 Gb per second per lane—a figure that doubles when using both lanes. This backward compatibility with UFS 3.1, alongside new features like the high-speed link startup sequence, significantly reduces the time for link startup by about 70% compared to conventional methods. Kioxia claims the new UFS 4.0 devices offer approximately 100% faster sequential read and about 40% faster sequential write speeds than competing solutions.

These advancements are further complemented by the refresh feature, which enhances data reliability, and the extended diagnosis feature, which provides protection and transparency into vehicle memory.

What Is UFS 4.0?

UFS 4.0 represents a significant advancement in Flash storage technology, tailored for the demands of the 5G era. As a Jedec-defined standard, UFS 4.0 offers substantial improvements over its predecessors and the older eMMC Flash storage standards, primarily in terms of data transfer speeds, power efficiency, and reliability.

One of the key differentiators of UFS 4.0 is its full-duplex interface, which enables simultaneous reading and writing operations. This is a notable advancement from the eMMC's half-duplex interface, which can only handle read or write tasks separately. This capability helps to both enhance the efficiency of data handling and significantly increase the speed at which data can be accessed and stored.

Kioxia's UFS product roadmap.

UFS 4.0 also supports two lanes of data transfer, enabling it to achieve data transfer rates of up to 5800 MBps and dwarfing the maximum 400 MBps speeds attainable by eMMC. This dual-lane architecture marks a substantial leap forward in Flash storage performance.

The introduction of UFS 4.0 is particularly timely, coinciding with the widespread adoption of 5G technology. With speeds of up to 2900 MBps per lane, UFS 4.0 doubles the rate of the previous UFS 3.1 standard, meeting the need for high-speed data access and storage in 5G devices.

UFS 4.0 incorporates enhanced security features, such as data encryption and replay-protected memory block (RPMB), to safeguard data confidentiality and prevent replay attacks. These security measures are crucial in today's digital age, where data breaches and eavesdropping are significant concerns.

Now Available for Sampling

Boasting full-duplex interfaces, blazing data transfer rates, and enhanced security features, Kioxia's UFS 4.0 devices mark a significant advancement in Flash storage technology. While the devices are currently available for sampling, Kioxia has yet to release dates for mass production.

All images used courtesy of Kioxia.