Vehicle Black Box Storage Endurance via Pseudo-TLC

Solution Overview

Problem

Conventional storage devices optimized for cost may not meet the high endurance requirements of black box event data recorders, while devices designed for endurance often include excessive memory, increasing costs unnecessarily.

Innovation Solution

Implementing a pseudo-TLC programming scheme with reduced program states and increased parity bits, along with optimized error correction mechanisms, to enhance the endurance of storage devices without adding additional memory, thereby achieving a balance between cost and endurance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If storage devices use conventional programming schemes optimized for cost, then memory capacity is maximized, but endurance is insufficient for black box requirements

Engineering Contradiction:

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent changes the programming parameters by using pseudo-TLC scheme with reduced program states (from 8 states in conventional TLC to 4 states), which modifies the electrical stress characteristics during programming and erasing operations. This parameter change reduces wear on memory cells while maintaining adequate storage capacity, thereby improving endurance without sacrificing too much memory capacity.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If storage devices increase memory capacity to meet endurance requirements, then endurance is improved, but cost increases unnecessarily

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

By changing the programming scheme parameters to pseudo-TLC with reduced program states, the patent achieves better endurance characteristics without needing to increase memory capacity. The modified programming approach reduces cell wear per operation, allowing the same memory capacity to achieve the required 1,400 TBW endurance rating.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses partial action by implementing error correction mechanisms that correct only the most critical errors that affect endurance, rather than attempting to correct all possible errors. This selective approach improves endurance effectiveness while avoiding the overhead costs of comprehensive error correction.

Inventive Principle:

Principle #16Partial or excessive action

3Reliability

If storage devices implement pseudo-TLC programming with reduced program states, then endurance is improved, but manufacturing complexity increases

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the programming process into distinct phases: initial programming using reduced program states, verification phase, and error correction phase. This segmentation allows each phase to be optimized independently, managing the overall complexity while achieving improved endurance through the pseudo-TLC approach.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS11061768B1Storage device with increased endurance

Publication Date: 2021.07.13

AI summary

A black box device for a vehicle includes a data storage system for recording event data fed to the black box from various vehicle sensors. The data storage system includes a memory having memory cells and a controller in communication with the memory. The controller is configured to receive data and determine one or more memory cells as a destination for the data to be written. The controller is configured to determine a wear level of the memory cells and select a subset of program states of the memory cells based on the wear level; and program the memory cells using respective subsets of program states for each respective memory cell.