Soft information generation for memory systems

摘要

Implementations include systems, methods and/or devices suitable for use in a memory system that use error control codes to improve the reliability with which data can be stored and read. Some implementations include systems, methods and/or devices enabled to generate and utilize soft information for decoding encoded data read from a storage medium. More specifically, some implementations utilize a collection of characterization vectors that include soft information values for bit-tuples that may be read from the storage medium for various combinations of the storage medium characterization parameter values. Some implementations are enabled to determine and utilize read comparison signal values associated with one or more storage medium characterization parameter values. And some implementations are enabled to determine and utilize shifted read comparison signal values associated with one or more storage medium characterization parameter values and an identified error condition.

主权项

1. A method of generating soft information values for data read from a storage medium, the method comprising:
retrieving a characterization vector, of a plurality of distinct characterization vectors that each includes a set of soft information values, wherein the characterization vector retrieved is based on a set of one or more storage medium characterization parameter values for the storage medium including an indicator of a number of previous program/erase cycles of a storage medium location being accessed; and in response to a read data request:
generating a first plurality of soft information values corresponding to a first plurality of data values read from a first portion of the storage medium and the retrieved characterization vector;obtaining an error indicator that indicates that the first plurality of soft information values are representative of data that includes at least one uncorrectable error; andgenerating a second plurality of soft information values corresponding to a second plurality of data values read from the first portion of the storage medium and the retrieved characterization vector, wherein, the second plurality of soft information values are generated in response to receiving the error indicator, and the second plurality of data values is distinct from the first plurality of data values; wherein the retrieved characterization vector includes soft information values from which the first plurality of soft information values and the second plurality of soft information values are generated.