Dynamic voltage allocation with quantized voltage levels and simplified channel modeling

After numerous program and erase (P/E) operations the Flash memory read channel experiences significant degradation, especially after certain retention time. As the volume of data programmed and erased from the device increases, successful recovery of the stored data becomes more difficult. Dynamic voltage allocation (DVA) allocates the write threshold voltages of each level as a function of the current degree of channel degradation to increase the lifetime of Flash memory. Several real-world constraints can limit the performance of DVA in practical Flash systems. This paper proposes specific solutions to address two major constraints: imperfect channel modeling and quantized voltage levels. The resulting implementation provides performance close to that of idealized settings.