Flash Memory Data Preservation During Solder Reflow

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Multi-level cell flash memory experiences data corruption and loss during the solder reflow process due to high temperature heating, leading to memory malfunctions and increased production costs.

Innovation Solution

The method involves preloading data into strong pages of flash memory blocks before the solder reflow process and reorganizing it according to a trigger signal, storing the data in both strong and weak pages to prevent loss, using a controller to manage the process and ensure data integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If multi-level cell flash memory is used to increase storage density, then storage capacity is improved, but data reliability deteriorates due to data loss during solder reflow process

Engineering Contradiction:

Improvestorage densityVSAvoiddata reliability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent applies preliminary action by copying data to strong pages before the solder reflow process. The controller detects soldering temperature and proactively copies data from weak pages to strong pages in advance, preventing data loss before it occurs during the high-temperature soldering process.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements beforehand cushioning by creating redundant data copies in strong pages before the harmful soldering process. These strong pages serve as a protective buffer that ensures data survival even if the original weak pages are corrupted during soldering.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

2Productivity

If data is stored in weak pages to maximize storage utilization, then storage efficiency is improved, but data loss occurs during high temperature soldering

Engineering Contradiction:

Improvestorage efficiencyVSAvoiddata loss

Core Design Contradiction:

ProductivityVSLoss of information

Solution Approach 1:

The controller performs preliminary data copying from weak pages to strong pages before soldering begins. This advance action ensures that even though weak pages are used for storage, the data is protected by creating a backup in temperature-resistant strong pages beforehand.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent uses copying by creating duplicate data copies in strong pages. The controller reads data from weak pages and writes copies to strong pages, ensuring data preservation through redundancy rather than relying solely on the original storage location.

Inventive Principle:

Principle #26Copying

3Ease of manufacture

If solder reflow process is performed to assemble memory components, then manufacturing is completed, but data corruption occurs due to high temperature heating

Engineering Contradiction:

Improvemanufacturing completionVSAvoiddata integrity

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The controller detects the soldering temperature and proactively copies data to strong pages before the high-temperature soldering process completes. This preliminary protective action occurs during the manufacturing process itself, ensuring data integrity is maintained through the soldering operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The strong pages act as an intermediary protective layer between the data in weak pages and the harmful high-temperature soldering process. The controller uses strong pages as a buffer zone that can withstand soldering temperatures while protecting the original data.

Inventive Principle:

Principle #24Intermediary (Mediator)

4Reliability

If data reorganization is performed after soldering to restore data, then data recovery is achieved, but production time is increased

Engineering Contradiction:

Improvedata recoveryVSAvoidproduction time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent performs data copying to strong pages during the soldering process itself rather than as a separate post-soldering step. This preliminary action during manufacturing minimizes additional production time while ensuring data recovery capability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The controller continuously monitors temperature and performs data copying operations during the soldering process without interrupting the manufacturing flow. This continuous operation ensures data protection is integrated into the manufacturing process rather than being a separate time-consuming step.

Inventive Principle:

Principle #20Continuity of useful action

Data Source

PatentUS8429334B2Method for preventing data loss during solder reflow process and memory device using the same

Publication Date: 2013.04.23 SILICON MOTION INC

AI summary

The invention provides a method for preventing data loss in a flash memory during a solder reflow process. The flash memory includes a plurality of memory blocks and each memory block includes a plurality of strong pages and weak pages. Preloading data is first received and stored into the strong pages of at least one of first memory block within the flash memory. Then, the flash memory is heated for the solder reflow process. Next, the preloading data is reorganized according to a trigger signal and the strong pages and weak pages of at least one of second memory block within the flash memory are provided for storing the reorganized preloading data.