Flash Memory Soft Information Generator for Data Link Throughput

Solution Overview

Problem

Conventional flash-memory devices experience reduced throughput and impaired read performance due to the increased data traffic caused by transferring multiple data bits for error correction, which is necessary to accurately read and store data reliably.

Innovation Solution

A flash-memory device that generates and transfers soft information within the device, rather than multiple data bits, to a memory controller for iterative decoding, thereby reducing the number of bits transmitted and improving data link efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple data bits are transferred for error correction, then data reliability is improved, but data link throughput deteriorates

Engineering Contradiction:

Improvedata reliabilityVSAvoiddata link throughput

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent extracts only the essential error correction information (soft information) from the multiple data bits read from flash memory cells, rather than transferring all raw data bits to the memory controller. This selective extraction reduces the data volume on the data link while preserving the necessary information for reliable error correction through iterative decoding.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent transforms the data representation from hard decision data bits to soft information with reliability metrics. By changing the parameter format from binary decisions to probabilistic information (such as log-likelihood ratios), the system enables more efficient error correction with reduced data transmission requirements, improving throughput while maintaining reliability.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If multiple reads of flash-memory cells are performed, then measurement precision is improved, but data traffic increases

Engineering Contradiction:

Improvecharge level measurement accuracyVSAvoiddata traffic

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent extracts only the essential error correction information (soft information) from the multiple data bits read from flash memory cells, rather than transferring all raw data bits to the memory controller. This selective extraction reduces the data volume on the data link while preserving the necessary information for reliable error correction through iterative decoding.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of transferring all raw read data from multiple reads to the controller for processing, the patent inverts the approach by generating soft information locally in the flash memory device and transferring only this compressed representation. This reversal significantly reduces data traffic while maintaining the precision benefits of multiple reads.

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS8947929B1Flash-based soft information generation

Publication Date: 2015.02.03 MARVELL ASIA PTE LTD

AI summary

The present disclosure describes techniques for flash-based soft information generation. In some aspects a flash-memory device includes a soft information generator configured to determine soft information for a data value stored by a flash-memory cell. The soft information includes fewer bits than a number of data bits read from the flash-memory cell from which the soft information is generated. When the flash-memory device transfers the soft information to a memory controller, fewer bits per data value are transferred. By so doing, an efficiency of a data link between the flash memory device and the memory controller may be improved.