Flash Memory Refresh via Host Command and Performance Feedback

Solution Overview

Problem

Existing flash memory technologies struggle to comprehensively address issues such as data retention, read disturb, write disturb, and wear-out, leading to errors and performance degradation over time.

Innovation Solution

A method and system for refreshing flash memory devices, where a host sends a refresh command to the flash memory device's main control unit, forcing it to stop current operations and execute a refresh operation on all valid data blocks, thereby enhancing data retention and overall performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by stationary object

If flash memory stores data for long periods without power, then power consumption is reduced, but data retention deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoiddata retention

Core Design Contradiction:

Use of energy by stationary objectVSReliability

Solution Approach 1:

The system performs preliminary refresh operations on flash memory blocks before data retention degradation occurs. The host device sends refresh commands to the flash memory device at scheduled intervals or when performance thresholds are met, proactively maintaining data integrity without requiring continuous power consumption for retention.

Inventive Principle:

Principle #10Preliminary action

2Reliability

If refresh operation is performed continuously, then data retention is improved, but productivity deteriorates

Engineering Contradiction:

Improvedata retentionVSAvoidoperation efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

Instead of continuous refresh operations, the system implements periodic refresh cycles where the host device sends refresh commands at predetermined time intervals or when performance thresholds are met. This periodic approach maintains data retention while allowing the flash memory to perform other operations during non-refresh periods, thereby improving overall productivity.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The flash memory device provides performance feedback to the host device, including performance values and thresholds. The host device uses this feedback to determine when refresh operations are necessary, dynamically adjusting refresh timing based on actual performance conditions rather than using fixed continuous schedules, thus optimizing the balance between data retention and productivity.

Inventive Principle:

Principle #23Feedback

3Reliability

If all data blocks are refreshed immediately, then data retention is improved, but use of energy deteriorates

Engineering Contradiction:

Improvedata retentionVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by stationary object

Solution Approach 1:

The system performs preliminary refresh operations on flash memory blocks before data retention degradation occurs. The host device sends refresh commands to the flash memory device at scheduled intervals or when performance thresholds are met, proactively maintaining data integrity without requiring continuous power consumption for retention.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The flash memory device provides performance feedback to the host device, including performance values and thresholds. The host device uses this feedback to determine when refresh operations are necessary, dynamically adjusting refresh timing based on actual performance conditions rather than using fixed continuous schedules, thus optimizing the balance between data retention and productivity.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS20250087280A1Method and system for refreshing flash memory device

Publication Date: 2025.03.13 INNODISK CORP

AI summary

A method and a system for refreshing a flash memory device are provided. The system mainly includes a host, and a main control unit and a plurality of flash memory units arranged in the flash memory device. The method includes the following steps: providing a performance value of the plurality of flash memory units from the main control unit to the host; providing a refresh command from the host to the main control unit when the performance value is lower than a pre-determined value; and controling the plurality of flash memory units, by the the main control unit, to stop current operations, and executing a refresh operation on the plurality of flash memory units.