Read Voltage Adjustment for Memory Storage Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional read voltage adjustment mechanisms fail to correct read voltage levels accurately in memory storage devices as they shift over time, leading to misjudgment of memory cell states and reduced service life.
Innovation Solution
A method that involves sending a write command sequence, followed by a read command sequence to obtain count information, and then adjusting the read voltage level based on the count information, compensation information, and default count information to improve correction efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional read voltage adjustment mechanism is used, then device complexity is reduced, but measurement precision of read voltage level deteriorates
Solution Approach 1:
The patent applies preliminary action by performing threshold voltage measurement and compensation information generation before actual data reading operations. The system pre-calculates compensation values based on measured threshold voltage distributions and stores them for later use during read operations, thereby improving read voltage level accuracy without adding complexity during the actual reading process
Solution Approach 2:
The patent implements feedback by measuring the actual threshold voltage of memory cells and using this information to adjust the read voltage levels. The system continuously monitors threshold voltage shifts and applies compensation based on the measured deviations, creating a closed-loop system that maintains accurate read voltage levels over time
2Reliability
If default read voltage levels are used, then ease of operation is improved, but reliability of data reading deteriorates
Solution Approach 1:
The patent applies self-service by enabling the memory system to automatically measure its own threshold voltage and generate compensation information without external intervention. The system self-adjusts the read voltage levels based on its own characteristics and usage history, eliminating the need for manual configuration while maintaining high reading reliability
Solution Approach 2:
The patent changes the parameter of read voltage level dynamically based on measured threshold voltage shifts. Instead of using fixed default voltage levels, the system adjusts voltage parameters in real-time according to the actual state of memory cells, thereby maintaining data reading accuracy without requiring complex user configuration
3Loss of information
If read voltage level is not adjusted, then device complexity is reduced, but loss of information increases
Solution Approach 1:
The patent performs preliminary threshold voltage measurement and compensation calculation before data reading operations. By pre-determining the appropriate read voltage levels based on measured threshold distributions, the system prevents information loss during reading without adding complexity during the actual data retrieval process
Solution Approach 2:
The patent introduces compensation information as an intermediary element between the raw threshold voltage measurements and the final read voltage levels. This intermediary compensation data serves as a bridge that translates measured voltage characteristics into accurate read voltage settings, reducing read errors while managing system complexity
Data Source
AI summary
A read voltage adjustment method, a memory storage device, and a memory control circuit unit are disclosed. The method includes: sending a write command sequence instructing to program a plurality of first memory cells in a rewritable non-volatile memory module; sending a first read command sequence instructing to read the programmed first memory cells using a first read voltage level to obtain first count information; obtaining first compensation information corresponding to the first read voltage level, wherein the first compensation information reflects a deviation in evenly programming the first memory cells to a plurality of states; and adjusting the first read voltage level according to the first count information, the first compensation information, and default count information corresponding to the first read voltage level.