SanDisk has announced plans to ship an ultra-dense form of NAND flash memory that could herald a breakthrough in storage.

Called X4, the technology uses a special memory controller that maintains data traffic speed while still fitting four bits of data per cell.

The method allows SanDisk – and Toshiba – to place 8GB of memory on a single chip, twice as much as before.

It does this while still maintaining a transfer speed of 7.8MB per second.

Since it is common to find four of these chips stacked together in a single package, the technology potentially doubles the amount of storage available on a high-end flash memory die to 64GB.

But it should remains small thanks to SanDisk’s more recent 43 nanometer manufacturing process.

Toshiba began making 32GB packages at the end of last year.

SanDisk expects the first X4-based products to be available in the first half of 2009, with memory cards being the most immediately recognizable offerings.

It’s not clear if the technology will be adopted in third-party products containing the larger-capacity flash.

Toshiba has supplied Apple with memory for the iPhone and iPod touch as well as other competing device makers.

Subscribe to our Newsletter