Performance in reading memory cells affected by neighboring memory cells
US10884855B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 2019 |
| Grant date | Jan 5, 2021 |
| Priority date | — |
| Expiry date | Aug 14, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2029/0411
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A storage device includes circuitry and memory cells that store data in Np programming levels of threshold voltage values. The circuitry defines NRv threshold-sets, each includes Ns read thresholds that define Ns+1 zones, produces Ns readouts by reading, from a target WL, using the NS read thresholds, a target page that was stored encoded using an Error Correction Code (ECC), and produces a reference readout by reading the target page using optimal read thresholds. The circuitry identifies Np programming levels of memory cells in a neighbor WL for classifying target cells in the target WL into Np·NRv cell-groups. The circuitry calculates, per zone, Np LLR values, for the respective Np programming levels, based on the reference readout, the Ns readouts and the classification, assigns the LLR values to the target cells, and recovers the target page by applying to the assigned LLR values soft decoding for decoding the ECC.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.