Host Data Access Control Using Targeted LDPC Re-Decoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Access management of memory devices using degraded flash memory dies is complicated due to unstable characteristics and prone to data errors, leading to reduced performance and prolonged recovery times for uncorrectable errors.
Innovation Solution
A method and apparatus for data access control using LDPC code decoding circuits to perform optimization procedures, including multiple decoding phases to identify and correct abnormal column segments, ensuring error-free data transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If degraded flash memory dies are used to reduce costs, then manufacturing cost is reduced, but data reliability deteriorates due to unstable characteristics and data errors
Solution Approach 1:
The code word is divided into multiple column segments, allowing selective processing of abnormal segments. This segmentation enables the system to handle degraded memory by focusing correction efforts on specific problematic segments rather than treating the entire data block uniformly.
Solution Approach 2:
The patent changes the decoding parameters dynamically by identifying abnormal column segments and adjusting the decoding strategy for these segments. The system modifies decoding parameters such as iteration counts and threshold values based on the detected error patterns in specific column segments.
2Reliability
If stronger data processing mechanisms are used to correct uncorrectable errors, then data correctness is improved, but processing time increases significantly
Solution Approach 1:
The patent applies partial action by performing LDPC decoding only on identified abnormal column segments rather than re-decoding the entire code word. This selective approach corrects errors in problematic segments while avoiding unnecessary processing of already-correct segments, significantly reducing overall processing time.
Solution Approach 2:
The system extracts and isolates abnormal column segments from the complete code word for targeted processing. By separating the problematic segments and handling them independently with appropriate decoding parameters, the system achieves efficient error correction without the time penalty of processing the entire data block.
3Reliability
If multiple decoding phases are implemented to ensure data correctness, then data reliability is improved, but system complexity increases
Solution Approach 1:
The patent implements dynamic decoding where the system adapts its processing approach based on real-time detection of abnormal column segments. The decoding process transitions between different phases (initial decoding, abnormal segment identification, targeted re-decoding) based on the actual error conditions detected in the data.
Solution Approach 2:
The system uses feedback from the initial decoding phase to identify abnormal column segments and adjust subsequent decoding operations. The feedback mechanism allows the system to detect decoding failures or error patterns in specific segments and trigger targeted re-decoding operations with modified parameters.
Data Source
AI summary
A method for performing data access control for a host device includes: receiving a plurality of host commands from the host device, for performing data access on at least one medium according to the plurality of host commands, wherein the data access includes data receiving; and performing a data access optimization procedure for maintaining correctness of the data receiving that includes: performing the data receiving on the at least one medium to obtain at least one code word; performing multiple first low-density parity-check (LDPC) code decoding operations regarding multiple column segments, where a portion of column segments are abnormal column segments corresponding to puncture variable nodes; finding at least one column segment satisfying predetermined selection condition, to perform at least one second LDPC code decoding operation regarding the at least one column segment; performing multiple third LDPC code decoding operations regarding the multiple column segments; and returning error-free data.