Non-Volatile Memory Page Buffer Retention for MLC Data Integrity

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In multi-level cell (MLC) non-volatile memory devices, the programming of most significant bit (MSB) page data can disturb previously programmed least significant bit (LSB) page data, leading to data loss if MSB programming fails.

Innovation Solution

A method and apparatus for managing a page buffer in non-volatile memory devices that retain LSB page data until MSB page data is successfully programmed, using a control block to determine the programming status of MSB data and release the LSB data only when successful, and to recover and reprogram LSB data if MSB programming fails, identifying affected blocks as bad blocks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If LSB page data is programmed to memory cells first, then MSB page data is programmed subsequently, then storage density is increased, but LSB page data may be disturbed or lost if MSB programming fails

Engineering Contradiction:

Improvestorage densityVSAvoiddata integrity

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent applies preliminary action by retaining the LSB page data in the page buffer before MSB programming is completed. This ensures that if MSB programming fails, the LSB data is still available in the buffer for recovery and reprogramming, preventing data loss while maintaining the high-density MLC storage structure

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements beforehand cushioning by using the page buffer as a protective buffer that holds LSB data during the MSB programming process. This buffer acts as a safety cushion that prevents direct loss of LSB data if MSB programming fails, allowing for error recovery without requiring additional backup storage

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Reliability

If LSB page data is retained in the page buffer until MSB programming is successful, then data integrity is maintained, but buffer memory is occupied longer

Engineering Contradiction:

Improvedata integrityVSAvoidbuffer occupancy time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent applies feedback by continuously monitoring the MSB programming status and using this information to control when to release the LSB page data from the buffer. The buffer retains data only until programming completion is confirmed, then releases it for new operations, optimizing buffer utilization while ensuring data integrity through status-dependent control

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS8614913B2Method and apparatus for controlling page buffer of non-volatile memory device

Publication Date: 2013.12.24 SAMSUNG ELECTRONICS CO LTD

AI summary

A method of managing a page buffer of a non-volatile memory device comprises programming least significant bit (LSB) page data from an LSB page buffer into a page of memory cells, and retaining the LSB page data in the LSB page buffer until most significant bit (MSB) page data corresponding to the LSB page data is programmed in the page.