Flash Memory Device Empty Page Detection via Boundary Reporting

Solution Overview

Problem

Conventional flash memory controllers face power consumption and computational complexity issues when suddenly powered off and then turned on again, as they need to determine which page units in a block are empty by sending multiple read commands to the flash memory device.

Innovation Solution

A flash memory device with an input/output control circuit, command register, address register, memory cell array, address decoder, status register, and control circuit, which allows the flash memory controller to send specific boundary check command signals or set-feature signals to determine whether multiple page units in a block are empty pages without the need for the flash memory controller to check the data itself.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the flash memory controller sends multiple read commands to determine empty page units, then the accuracy of identifying empty pages is improved, but the power consumption and computational complexity of the controller increase

Engineering Contradiction:

Improveaccuracy of identifying empty pagesVSAvoidpower consumption of controller

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The flash memory device performs self-service by autonomously determining whether page units are empty pages through its internal control circuit, and reporting the boundary position information to the controller. This eliminates the need for the controller to send multiple read commands and perform complex computations, thereby reducing the controller's power consumption while maintaining accurate identification of empty pages.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The invention extracts the empty page determination function from the flash memory controller and relocates it to the flash memory device. The control circuit in the flash memory device now handles the reading and determination of empty pages, while the controller only needs to receive and process the reported boundary position information, significantly reducing the controller's computational burden and power consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If the flash memory controller checks multiple page data to determine empty pages, then the completeness of empty page identification is improved, but the computational complexity of the controller increases

Engineering Contradiction:

Improvecompleteness of empty page identificationVSAvoidcomputational complexity of controller

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The flash memory device performs self-service by autonomously determining whether page units are empty pages through its internal control circuit, and reporting the boundary position information to the controller. This eliminates the need for the controller to send multiple read commands and perform complex computations, thereby reducing the controller's power consumption while maintaining accurate identification of empty pages.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The invention extracts the empty page determination function from the flash memory controller and relocates it to the flash memory device. The control circuit in the flash memory device now handles the reading and determination of empty pages, while the controller only needs to receive and process the reported boundary position information, significantly reducing the controller's computational burden and power consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

3Ease of operation

If the flash memory controller determines empty pages by itself, then the independence of the controller is improved, but the operation time and efficiency decrease

Engineering Contradiction:

Improveindependence of controllerVSAvoidoperation time for empty page determination

Core Design Contradiction:

Ease of operationVSLoss of time

Solution Approach 1:

The flash memory device performs self-service by autonomously determining whether page units are empty pages through its internal control circuit, and reporting the boundary position information to the controller. This eliminates the need for the controller to send multiple read commands and perform complex computations, thereby reducing the controller's power consumption while maintaining accurate identification of empty pages.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS12265728B2Scheme for finding and checking whether page units in one block are empty pages by using flash memory device and reporting fund result from flash memory device to flash memory controller

Publication Date: 2025.04.01 SILICON MOTION INC

AI summary

A flash memory controller is used in a storage device and coupled to a flash memory device of the storage device through a specific communication interface and includes an input/output (I/O) circuit and a processor. The I/O circuit is coupled to the flash memory device through the specific communication interface, and used for sending commands and data between the flash memory device and the processor. The processor is used for controlling the I/O circuit sending a specific boundary check command signal or a specific boundary check set-feature signal via the specific communication interface to the flash memory device, to make the flash memory device read out more page data of multiple page units from a specific block in the memory cell array and to make the flash memory device determine whether the multiple page units are empty pages.