Yesterday, the Open NAND Flash Interface (ONFI) Working Group (wow, that’s a mouthful) released a new 3.0 standard for its NAND interface. The updated standard offers higher speeds in addition to features that should allow SSD makers to build drives more cheaply. By far the biggest improvement is the use of a new non-volatile DDR2 interface that allows individual NAND chips to push data at up to 400MB/s. This doubles the previous ONFI specification’s maximum transfer rate of 200MB/s.
Thanks to the faster interface, SSDs should be able to maintain current performance levels while using fewer channels. This should lead to cheaper drives that contain fewer chips. The ONFI 3.0 spec also reduces the number of chip-enable and controller pins required for those chips. Lowering the pin counts makes associated circuit boards less complex, a move that should further reduce costs.
Future versions of the ONFI standard will support ECC Zero (EZ-NAND), which moves error correction from the SSD controller to the NAND chips. There’s no word on when this useful feature will be added, though. We do know that the first drives using ONFI 3.0 NAND aren’t expected to show up until next year. SandForce has pledged to deliver solutions using the interface in 2012.