Interference compensation technique for multilevel flash memory

Abstract

Multilevel cell flash memory devices are galUlUg popularity because it can increase the memory capacity by storing two or more bits to a single cell. However, when the number of levels of a cell increases, the inter-cell interference which shifts cell (threshold) voltage becomes more critical. Thereare two approaches to alleviate the errors caused by the voltage shift.One is the error correcting codes, and the other is the signal processing methods. We focus on signal processing methods to reduce the cell to cell interference which causes the voltage shift, and propose algorithms which reduce the voltage shift effects by cIassfying and compensating erratic cells. The simulation resultsshow that the proposed algorithms are effective for interference reduction.

Improving flash memory reliability with dynamic thresholds: Signal processing and coding schemes

“…From other aspects, there are several analyses and models on the flash storage channel, and some other attempts such as signal processing techniques [9], [10], innovative programming schemes [11] and special floating gate architectures [12], [13] are proposed for future generations of flash.…”