SanDisk announces 400GB micro-SDXC memory card

Western Digital subsidiary SanDisk has announced the world's highest-capacity micro-SDXC card which stores a whopping 400GB, just two years after launching a 200GB version.

Back in March 2015, SanDisk boasted of a micro-SDXC capacity high with a 200GB model priced at a US recommended retail price of $399.99 (around £311 excluding taxes). Now, two years later, the march of technology has not only resulted in double the capacity but a lower price: SanDisk's latest offers 400GB of storage at a US recommended retail price of $249.99 (around £194 excluding taxes).

'We continue to push technology boundaries and transform the way consumers use their mobile devices,' claimed Sven Rathjen, vice president of product marketing at SanDisk's parent company Western Digital. 'By focusing on achieving new technology milestones, we enable consumers to keep up with their mobile-centric lifestyles with storage solutions they trust.'

Sadly, and in keeping with its 200GB micro-SDXC launch two years ago, Rathjen and SanDisk have both been somewhat coy about exactly how the doubling in capacity has come about. According to Western Digital, it's simply a case of the company 'leveraging its proprietary memory technology and design and production processes that allow for more bits per die,' a non-statement which exactly mirrors that for the 200GB launch two years ago and the 128GB launch a year before that. Whether the 'proprietary memory technology' to which the company refers is the three-dimensional BiCS technology developed in partnership with Toshiba is not known.

SanDisk has claimed transfer speeds of up to 100MB/s in compatible devices, with the card meeting the SD Assocation's A1 App Performance Class specification which requires 1,500 random read input-output operations per second (IOPS) and 500 random write IOPS along with a minimum sustained sequential write of 10MB/s. It falls short, however, of the more demanding A2 App Performance Class which would require 4,000 random read and 2,000 random write IOPS - suggesting SanDisk has traded performance for capacity in its design.

SanDisk has set a $249.99 recommended retail price in the US, which has translated to a pre-order price of £224.99 at UK retailers. The company's two-year-old 200GB design, meanwhile, has dropped in price since launch to just £65.99, with its 256GB successor priced at £124.99.