SanDisk has also produced an advanced X4 controller, which is necessary to effectively manage the complexities and performance requirements of X4 memory. The X4 memory chip combines with the X4 controller chip in a multi-chip package (MCP) to provide a complete, integrated and low-cost storage solution.
At the 2009 International Solid State Circuits Conference (ISSCC), SanDisk and Toshiba presented a technical paper describing the key technology advancements that led to the development of 64Gb 4-bits-per-cell NAND flash memory on 43nm technology node. This announcement comes one year after SanDisk unveiled its X3 (3-bits-per-cell NAND) technology at the 2008 ISSCC and was subsequently honored with the ISSCC 2009 Lewis Winner Outstanding Paper Award.