Mobile iNAND UFS Series Embedded Flash Drives

UFS Embedded Flash Storage for Data-Intensive Mobile Devices


Robust, Reliable and Fast Edge Storage for a Mobile and Compute World

Mobile devices are smarter and faster than ever before. They offer both consumers and businesses unprecedented communication, productivity, and entertainment experiences, all enabled by the ability to easily capture, access, transform, and preserve data.

The iNAND MC EU311 and MC EU321 EFD (Embedded Flash Drive) are our most advanced flash storage solutions, built on the latest 3D NAND technology. Both offer exceptional read and write performance with SmartSLC and UFS 2.1. They are designed to deliver a fast, smooth user experience for the most data-intensive flagship mobile devices and tablets.


Performance for Mobile Devices

Leading 3D NAND Technology

Designed and developed by Western Digital, the iNAND MC EU321 is the industry’s first 96L 3D NAND embedded flash drive with firmware, assembly and testing

High Performance

Fast UFS interface, 5th generation SmartSLC and leading 3D NAND technology provides superior speed and high capacity for smartphones and tablets

Scalability & Design Flexibility

Capacities from 32GB up to 256GB in a small form factor, allowing for design flexibility and scalability; compatible with a wide range of host and JEDEC compliant devices


  • UFS 2.1 Gear3, 2-Lane
  • Designed for data intensive smartphones and tablets
  • iNAND MC EU321 EFD on industry leading 96L 3D NAND technology enables an exceptional mobile user experience with iNAND SmartSLC 5.1, maintaining high performance as the device approaches full capacity with superior and persistent write speeds
  • iNAND MC EU311 EFD with 5th generation SmartSLC offers greatly enhanced performance compared to previous generation e.MMC products
  • Capacities of 32GB to 256GB within a unified small form factor package of 11.5x13x1.0mm

Applications and Workload

  • Data-intensive high-end and flagship smartphones
  • Tablets
  • Chromebooks
  • Augmented Reality
  • Virtual Reality
  • Artificial Intelligence
  • 4K Video
  • Multiple high resolution cameras

3D NAND Enables Data to Thrive



Smartphones, tablets, and notebooks demand performance and high-capacity storage in a small footprint to enable the compelling devices we use today.

Western Digital’s embedded flash devices with UFS run our favorite applications, capture our photos, and store the videos that we carry and use everywhere and watch anytime.


Mobile iNAND UFS Series
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Fast Performance

5th Generation SmartSLC with up to 550 MB/s Sequential Write Speed2

High Quality

UFS controller, 3D NAND technology, firmware, assembly and testing designed and developed by Western Digital

Thin Form Factor

Z-height as low as 1.0mm




11.5x13x1.0mm (all capacities)

Part Numbers


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1GB = 1,000,000,000 bytes; the actual user capacity may vary depending upon the configuration


Up to the stated speed. Values derived from internal testing; performance may vary depending upon drive capacity, host device, OS and application.

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