US 2009/0292971 A1 · Data recovery techniques

Abstract

Techniques are described that include reading a portion of a memory and determining whether there is any uncorrectable codeword. Due to time varying errors present during a read operation, the uncorrectable codeword may become read as a correctable codeword at another time. If any uncorrectable codeword is present in the portion, the portion can be re-read to determine whether any uncorrectable codeword is instead correctable. Prior to re-reading the portion, a reference level used to determine whether a logic zero or one is stored can be adjusted. Adjusting the reference level can allow an uncorrectable codeword to become a correctable codeword.

Claims21

Dependent claims

A method comprising:

reading data from a memory segment;
determining whether any portion of the data includes an uncorrectable codeword;
and
selectively re-reading the memory segment in response to the portion of the data including the uncorrectable codeword, wherein the re-reading comprises adjusting at least one parameter used to evaluate contents of the memory segment.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

12/288,617Filed 22 Oct 2008

Priority

21 May 2008

Published

26 Nov 2009

Term ends

Not estimatedThe source records don’t support an estimate.

Classification7 codes

G11C 7/14
Arrangements for writing information into, or reading information out from, a digital store: dummy cell management; Sense reference voltage generators
G06F 11/1068
In individual solid state devices: in sector programmable memories, e.g. flash disk
G11C 7/08
Sense amplifiers; Associated circuits , e.g. timing or triggering circuits: control thereof
G11C 16/26
Auxiliary circuits, e.g. for writing into memory: sensing or reading circuits; Data output circuits

Data recovery techniques

Life of this patent

Data recovery techniques

Life of this patent

Abstract

Claims21