Samsung 840 White Paper page 16

So why choose one standard over the other? The latest ONFI NAND chips, because ONFI has alternated between
synchronous and asynchronous methods, must be built with backwards compatibility for both synchronous and
asynchronous logic. Because Toggle NAND has always been asynchronous, Toggle 2.0 NAND benefits from reduced
complexity and, in turn, increased flexibility when it comes to designing smaller chip sizes and bringing next-generation
products to market faster. Furthermore, because of Samsung and Toshiba's positions as market leaders in the NAND
industry, a majority of the market has standardized on Toggle NAND.
NAND Type & Performance
How do speed differences among the various generations of individual NAND chips affect the overall speed of an SSD?
And what does this mean for you in terms of real-world impact?
In practice, the use of synchronous versus asynchronous NAND has no impact on SSD performance. What actually affects
performance is the generation of the NAND (e.g. SDR/ONFI 1.0, Toggle 1.0/ONFI 2.0, etc.). When discussing NAND type,
therefore, it is inaccurate to refer to it simply as either "synchronous" or "asynchronous" when referring to performance.
Why Samsung?
As the #1 player in the worldwide memory market for over 20 years, no one has more experience manufacturing NAND
than Samsung. Furthermore, Samsung's fully-integrated manufacturing approach means that it has intimate knowledge
of every nuance of each component of your SSD. While generic controller manufacturers must optimize their chips
to work with both ONFI and Toggle NAND, Samsung can focus all of its design efforts on making Toggle NAND work
perfectly with its proprietary controller technology. The end result is product characterized by awesome performance
and unrivaled reliability – a product only Samsung could build.