Kioxia Mass Producing QLC UFS V.4.0 Up to 512GB Embedded Flash Memory Devices

Kioxia America, Inc. has begun mass production of the industry’s 1st ⁽¹⁾ Universal Flash Storage (UFS) ⁽²⁾ Ver. 4.0 embedded flash memory devices with 4-bit-per-cell, QLC technology.

QLC UFS offers a higher bit density than traditional TLC UFS, making it for mobile applications that require higher storage capacities. Advancements in controller technology and error correction have enabled QLC technology to achieve this while maintaining competitive performance. The company’s 512GB QLC UFS achieves sequential read speeds of up to 4,200MB/s and sequential write speeds of up to 3,200MB/s, taking advantage of the UFS 4.0 interface speed.

The QLC UFS is for smartphones and tablets, as well as other next-gen applications where higher storage capacity and performance are key considerations – including PCs, networking, AR/VR, IoT, and AI.

Key features include:

• Supports High Speed Link Startup Sequence (HS-LSS) features: With conventional UFS, Link Startup (M-PHY and UniPro initialization sequence) between device and host is performed at low-speed PWM-G1 (3~9Mb/s), but with HS-LSS, it can be performed at a faster HS-G1 Rate A (1,248Mb/s). This is expected to reduce the time for Link Startup by approximately 70% compared to the conventional method.
• Enhances security: By utilizing Advanced RPMB (Replay Protected Memory Block) for improved RW access to security data, such as user credentials on RPMB area, and RPMB Purge to ensure discarded data may be sanitized securely and rapidly.
• Supports Extended Initiator ID (Ext-IID): Intended to be used with Multi Circular Queue (MCQ) at the UFS 4.0 host controller for improved random performance.

The company was the 1st to introduce UFS technology ⁽³⁾, and continues to develop new flash products. The QLC UFS Ver. 4.0 device integrates the firm’s BiCS FLASH 3D flash memory and a controller in a JEDEC standard package. UFS 4.0 incorporates MIPI M-PHY 5.0 and UniPro 2.0 and supports maximum theoretical interface speeds of up to 23.2Gb/s per lane or 46.4Gb/device. UFS 4.0 is backward compatible with UFS 3.1.

“Kioxia’s introduction of the industry’s first QLC UFS Ver. 4.0 devices underscores our commitment to pushing the boundaries of storage technology,” said Maitry Dholakia, VP, memory business unit. “By leveraging QLC technology, we are able to deliver higher densities and cost efficiencies, enabling our customers to meet the growing demands of today’s data-intensive applications while maintaining exceptional performance standards.”

⁽¹⁾ Industry first claim based on Kioxia survey of publicly available information as of October 29, 2024
⁽²⁾ Universal Flash Storage (UFS) is a product category for a class of embedded memory products built to the JEDEC UFS standard specification. Due to its serial interface, UFS supports full duplexing, which enables both concurrent reading and writing between the host processor and UFS device.
⁽³⁾ Kioxia Corporation’s 1st sample shipment, as of February 8, 2013.