Targeted Auto Read Calibrate for Memory Subsystems

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Memory sub-systems, such as solid-state drives, often fail to correctly read data due to changes in temperature or degradation of charge levels in memory cells, leading to longer read retry processes with conventional auto read calibrate operations.

Innovation Solution

Implementing a targeted auto read calibrate operation that selects a baseline threshold voltage set based on syndrome weights generated by an error correction component, reducing the execution of unnecessary auto read calibration operations and shortening the read retry process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional auto read calibrate operations are executed, then data recovery is attempted, but the read retry process becomes longer and less efficient

Engineering Contradiction:
Improvedata recovery successVSAvoidread retry process time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary actions by executing read retry operations with multiple threshold voltage sets before initiating auto read calibrate operations. Syndrome weights are generated and stored in advance to guide subsequent calibration, ensuring that the calibration process starts with optimized parameters rather than brute-force searching, thereby reducing overall read retry time while maintaining data recovery reliability

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback mechanisms by using syndrome weights from read retry operations to dynamically adjust and select baseline threshold voltage sets for auto read calibrate operations. This feedback loop allows the system to learn from previous read attempts and optimize future calibration processes, reducing unnecessary calibration iterations and shortening the read retry process time

Inventive Principle:
Principle #23Feedback

2Reliability

If multiple auto read calibrate operations are executed, then read retry success rate improves, but unnecessary operations increase device complexity and time consumption

Engineering Contradiction:
Improveread retry success rateVSAvoidauto read calibrate operation complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system applies local quality by selecting specific baseline threshold voltage sets for auto read calibrate operations based on syndrome weight analysis rather than uniformly applying all possible calibration operations. This targeted approach ensures that calibration operations are localized to the most promising voltage ranges, reducing unnecessary operations and simplifying the overall process while maintaining high read retry success rates

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The system utilizes parameter changes by dynamically selecting and adjusting threshold voltage sets based on syndrome weights from read retry operations. This parameter optimization allows the system to focus calibration efforts on the most relevant voltage ranges, reducing the number of unnecessary calibration operations and simplifying the device complexity while preserving read retry effectiveness

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS10915395B2Read retry with targeted auto read calibrate
Publication Date: 2021.02.09 MICRON TECHNOLOGY INC
  • US10915395B2 patent drawing
  • US10915395B2 patent drawing
  • US10915395B2 patent drawing

AI summary

Various examples are directed to systems and methods for reading a memory component. A processing device may receive an indication that a read operation at a physical address of the memory component failed. The processing device may execute a plurality of read retry operations at the physical address. The processing device may access a first syndrome weight describing a first error correction operation performed on a result of a first read retry operation of the plurality of read retry operations and a second syndrome weight describing a second error correction operation performed on a result of a second read retry operation of the plurality of read retry operations. The processing device may select a first threshold voltage associated with the first read retry operation based at least in part on the first syndrome weight and the second syndrome weight. The processing device may also execute a first auto read calibrate operation at the physical address, the first auto read calibrate operation having a baseline at the first threshold voltage.