Memory Refresh Circuit With Process-Corner Adaptive Row Refresh

Solution Overview

Problem

Conventional refresh circuits waste current by sending refresh commands at fixed intervals, which can lead to unnecessary refresh operations under slower process corners, as they do not adjust the refresh execution proportion based on the process corner speed, resulting in inefficient energy usage.

Innovation Solution

A refresh circuit that includes a refresh control module to adjust the execution proportion of refresh commands based on the process corner signal, allowing for a higher execution proportion under faster process corners and a lower proportion under slower corners, thereby optimizing the refresh operation to prevent current wastage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If refresh commands are sent at fixed time intervals based on faster process corner requirements, then all row addresses can be refreshed within the shorter data hold time, but unnecessary refresh operations occur under slower process corners, wasting current

Engineering Contradiction:

Improvedata hold time complianceVSAvoidrefresh current consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The refresh control module dynamically adjusts the execution proportion of refresh commands based on the detected process corner. Under faster process corners, a higher proportion of refresh commands are executed to ensure all rows are refreshed within the shorter data hold time. Under slower process corners, a lower proportion is executed since the longer data hold time allows more relaxed refresh scheduling, thereby avoiding unnecessary refresh operations and reducing current consumption.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the execution proportion parameter of refresh commands according to the process corner detected. By adjusting this parameter dynamically - increasing it for faster corners and decreasing it for slower corners - the system optimizes the balance between meeting data hold time requirements and minimizing refresh current consumption.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a higher execution proportion of refresh commands is used under faster process corners, then all rows can be refreshed within the shorter data hold time, but current consumption increases

Engineering Contradiction:

Improverefresh completion within data hold timeVSAvoidrefresh current consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The refresh control module dynamically adjusts the execution proportion of refresh commands based on the detected process corner. Under faster process corners, a higher proportion of refresh commands are executed to ensure all rows are refreshed within the shorter data hold time. Under slower process corners, a lower proportion is executed since the longer data hold time allows more relaxed refresh scheduling, thereby avoiding unnecessary refresh operations and reducing current consumption.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the execution proportion parameter of refresh commands according to the process corner detected. By adjusting this parameter dynamically - increasing it for faster corners and decreasing it for slower corners - the system optimizes the balance between meeting data hold time requirements and minimizing refresh current consumption.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11817142B2Refresh circuit and memory

Publication Date: 2023.11.14 CHANGXIN MEMORY TECH INC

AI summary

Embodiments of the present application provide a refresh circuit and a memory. The refresh circuit includes: a refresh control module configured to receive and execute a refresh command to output a row address refresh signal; and further configured to receive a process corner signal to adjust an execution proportion of the refresh command, the faster a process corner represented by the process corner signal, the higher the adjusted execution proportion; a row addresser configured to receive the row address refresh signal and output a to-be-refreshed single-row address; and an array refresh device configured to perform a single-row refresh operation according to the single-row address and output a single-row refresh end signal after the end of single-row refresh. The embodiments of the present application help reduce the consumption of refresh currents.