DRAM Memory Cell with Programmable Impedance Shadow Element
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic random access memories (DRAMs) are volatile, requiring frequent refresh operations and losing data when power is removed, which can be costly and time-consuming to recover, especially in systems like data servers.
Innovation Solution
Incorporating programmable impedance elements that 'shadow' dynamic storage elements, allowing data to be stored nonvolatively when power is not available and loaded back into dynamic storage elements when needed, maintaining DRAM-like performance with added nonvolatility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If DRAM memory cells use dynamic storage elements (capacitors), then fast data access speeds and low power consumption are achieved, but data is lost when power is removed and frequent refresh operations are required
Solution Approach 1:
The memory cell is segmented into two distinct storage elements: a dynamic storage element (capacitor) for fast access operations and a static storage element (programmable metallization cell) for nonvolatile data retention. This segmentation allows each element to specialize in its respective function, resolving the contradiction between speed and reliability.
Solution Approach 2:
Before power removal, data is proactively transferred from the dynamic capacitor to the static programmable metallization cell. This preliminary action ensures data is preserved before the dynamic element loses its charge, preventing data loss without requiring external intervention after power failure.
2Use of energy by moving object
If DRAM memory cells use dynamic storage elements (capacitors), then low power consumption is achieved, but frequent refresh operations are required to maintain data
Solution Approach 1:
The memory system is divided into a dynamic region for active storage and a static region for archival storage. The static programmable metallization cells do not require refresh operations as they maintain data without power, eliminating the time loss associated with refreshing while keeping the dynamic elements available for fast access.
Solution Approach 2:
Data is copied from the dynamic capacitor to the static programmable metallization cell for preservation. This copying mechanism allows the original dynamic data to be maintained for fast access while creating a persistent backup that does not consume power or require refresh operations.
3Reliability
If separate nonvolatile storage is used to prevent data loss, then data retention is improved, but system complexity and data recovery time increase
Solution Approach 1:
The dynamic capacitor and static programmable metallization cell are merged into a single integrated memory cell structure. This unified cell combines the advantages of both storage types (fast access and nonvolatility) without requiring separate storage devices, thereby reducing system complexity while maintaining improved data retention.
Solution Approach 2:
The programmable metallization cell serves multiple functions: it acts as nonvolatile storage for data retention, provides backup during power failures, and enables fast data recovery. This multi-functionality eliminates the need for separate dedicated backup storage systems, reducing overall system complexity.
4Reliability
If separate nonvolatile storage is used to prevent data loss, then data retention is improved, but data recovery time after power failure increases
Solution Approach 1:
Data is preliminarily transferred to the static programmable metallization cell before power failure occurs. This preliminary action ensures data is already preserved in nonvolatile storage, eliminating the need for time-consuming data recovery operations after power restoration. The data is immediately available when power is restored.
Solution Approach 2:
A copy of the data is maintained in the static programmable metallization cell while the original remains in the dynamic capacitor. This copying strategy enables instantaneous data recovery after power failure by simply restoring power to the dynamic element, which will automatically retrieve data from its static backup without requiring lengthy reconstruction processes.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables data retention for extended periods without power, reducing the need for frequent refresh operations and minimizing data loss in power outages, while maintaining fast access speeds and low power consumption.
Implementation Method 1
Programmable impedance elements can 'shadow' the dynamic storage elements by storing the same data values as the dynamic storage elements
Implementation Method 2
Dynamic random access memories (DRAMs) include memory cells with dynamic storage elements (i.e., capacitors)
Implementation Method 3
data values can be loaded from the programmable impedance elements back into the dynamic storage elements
Data Source
AI summary
A memory device can include a plurality of memory cells, each including a dynamic section configured to store data dynamically, and a programmable impedance section comprising at least one programmable element programmable between at least two different data states, the programmable impedance section configured to establish a data value stored by the dynamic section in response to a recall signal.