Finding read disturbs on non-volatile memories
US9230689B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2014 |
| Grant date | Jan 5, 2016 |
| Priority date | — |
| Expiry date | Jun 27, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2211/5644
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In non-volatile memory devices, the accessing of data on word line can degrade the data quality on a neighboring word line, in what is called a read disturb. Techniques are presented for determining word lines likely to suffer read disturbs by use of a hash tree for tracking the number of reads. Read counters are maintained for memory units at a relatively coarse granularity, such as a die or block. When the counter for one of these units reaches a certain level, it is subdivided into sub-units, each with their own read counter, in a process that be repeated to determine frequently read word lines with a fine level of granularity while only using a relatively modest amount of RAM on the controller to store the counters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.