Flash Memory Read Retry Voltage Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Data storing systems face performance deterioration and reliability issues due to the need for repeated read operations in flash memory devices, which can lead to errors and inefficiencies in maintaining data integrity.
Innovation Solution
A data storing system and method that utilize a read retry table to adjust read voltages, storing data at multiple buffer positions and determining the optimal read voltage based on previous read operations to minimize the number of read attempts, thereby improving data reliability and reducing performance degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple read operations are performed with different read voltages to ensure data reliability, then data reliability is improved, but the number of read operations increases causing performance deterioration
Solution Approach 1:
The patent applies preliminary action by pre-establishing a read retry table that contains multiple read voltage values and their corresponding buffer positions before actual read operations occur. When a read operation fails, the system can immediately retrieve the next appropriate read voltage from the pre-configured table without performing complex real-time calculations, thus maintaining high data reliability while minimizing the performance impact of multiple read attempts
Solution Approach 2:
The patent implements parameter changes by systematically varying the read voltage parameter across multiple read operations. The read retry table stores different read voltage values (e.g., Vread1, Vread2, Vread3) that can be sequentially applied when initial read operations fail. This parameter variation allows the system to adapt to different threshold voltage distributions in flash memory cells, improving data reliability while the structured approach minimizes performance degradation
2Manufacturing precision
If read voltage level is adjusted frequently to handle threshold voltage distribution variations, then manufacturing precision is improved, but device complexity increases
Solution Approach 1:
The patent applies self-service by enabling the system to automatically select and adjust read voltage levels without requiring external intervention or complex control algorithms. The read retry table is pre-configured with appropriate voltage values and buffer positions, allowing the system to autonomously handle threshold voltage distribution variations by simply retrieving the next voltage from the table when a read operation fails, thus improving precision while keeping the control mechanism relatively simple
Solution Approach 2:
The patent implements feedback through the read retry mechanism where the system monitors read operation results and automatically adjusts the read voltage based on whether the previous read was successful. When a read operation fails to retrieve valid data, the system uses feedback from this failure to select the next read voltage from the read retry table, creating a closed-loop control system that improves threshold voltage distribution handling without requiring complex external control
Data Source
AI summary
A data storing system includes a semiconductor device suitable for repeatedly performing a read operation by changing a level of a read voltage according to read voltages listed on a read retry table when a read operation on a selected page is passed, in response to a command and an address, and a controller suitable for controlling the read operation of the semiconductor device by generating the command and the address, wherein a read voltage to be used for performing the read operation is determined among the read voltages listed on the read retry table when the semiconductor device performs the read operation based on data read as a result of a predetermined number of read operations.