Memory Read Retry Tables for Word-Line Voltage Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The read operation in storage devices fails due to changes in memory characteristics, leading to inefficiencies in data retrieval.
Innovation Solution
A storage device with a memory control system that utilizes a read retry table generated based on internal and external data, adjusting read voltages for individual memory cells to optimize read retry operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a preset read voltage is used for reading data from memory, then the read operation structure is simple, but the read operation fails due to changes in memory characteristics
Solution Approach 1:
The patent applies preliminary action by generating a read retry table in advance that stores optimal read voltages for different word lines and memory blocks. This table is created before actual read operations occur, allowing the system to quickly lookup and apply appropriate read voltages without real-time computation, thus improving read reliability while maintaining operational simplicity
Solution Approach 2:
The patent changes the read voltage parameter dynamically based on memory characteristics. Instead of using a fixed preset read voltage, the system selects different read voltages from the read retry table according to the specific word line and memory block being accessed, adapting to variations in memory characteristics to improve read success rate
2Reliability
If read retry operations are performed with fixed read voltages, then the control process is simple, but data retrieval fails when memory characteristics change
Solution Approach 1:
The read retry table is generated in advance and stored, containing pre-calculated optimal read voltages for various memory conditions. This eliminates the need for time-consuming real-time voltage optimization during read retry operations, reducing time loss while improving data retrieval reliability
Solution Approach 2:
The patent creates a copied representation of optimal read voltage settings in the read retry table, which is generated through initial characterization of the memory. This copied information allows rapid lookup during read operations without requiring repeated measurements or calculations, saving time while ensuring reliable data retrieval
3Measurement precision
If a read retry table is generated using only internal memory data, then the generation process is simple, but the table accuracy is insufficient for comprehensive memory variations
Solution Approach 1:
The patent merges internal memory data with external reference data to generate the read retry table. By combining information from multiple sources including different memory blocks and word lines, the system creates a more accurate and comprehensive read retry table that better captures memory variations, improving measurement precision while justifying the increased data collection complexity
Data Source
AI summary
An embodiment of the present disclosure may provide a read retry table optimized for a memory on the basis of a distribution of read voltages of word lines included in the corresponding memory, and by changing a method of setting a read retry table depending on the number of sample data, may provide an optimal read retry table even for a memory with insufficient sample data.