Deferred Fractional Row Activation in DRAM
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic random access memories (DRAMs) face a timing bottleneck due to the energy-intensive row activation process, where most transferred data during row activation remains untouched in subsequent column operations, leading to wasted power.
Innovation Solution
Implementing a deferred-activation mode where row activation operations are performed on fractions of storage rows (subrows) only when specific column commands are received, reducing power consumption without compromising memory bandwidth or increasing access latency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If row activation is performed on the entire storage row, then data is transferred to sense amplifiers for potential access, but power consumption increases significantly as most transferred data remains untouched
Solution Approach 1:
The patent divides the storage row into multiple subrows, each associated with separate sense amplifier banks. Instead of activating the entire row, only the specific subrow containing the requested data is activated. This segmentation allows selective data transfer to only the necessary sense amplifiers, reducing power consumption while maintaining data accessibility.
Solution Approach 2:
The patent implements different activation strategies for different portions of the storage row based on access patterns. By identifying which subrow contains the requested data and activating only that portion, the system applies local quality by treating each subrow differently rather than uniformly activating the entire row, thereby reducing unnecessary power consumption.
2Loss of time
If high row to column ratios are used to increase hit probability, then spatial/temporal locality is exploited for lower latency, but power is wasted activating data that is not accessed
Solution Approach 1:
By segmenting the row into subrows with dedicated sense amplifier banks, the patent enables selective activation of only the subrow containing the requested data. This maintains low latency by having ready-access data in the appropriate sense amplifier bank while avoiding the energy waste of activating other subrows whose data will not be accessed.
3Use of energy by moving object
If fractional row activation is implemented, then power consumption is reduced by activating only necessary data, but device complexity increases due to multiple sense amplifier banks
Solution Approach 1:
The patent organizes sense amplifiers into multiple banks, with each bank associated with a specific subrow. This segmentation, while increasing complexity, enables selective activation that significantly reduces power consumption. The structured organization of subrows and banks provides a systematic approach to managing the complexity.
Data Source
AI summary
Row activation operations within a memory component are carried out with respect to subrows instead of complete storage rows to reduce power consumption. Further, instead of activating subrows in response to row commands, subrow activation operations are deferred until receipt of column commands that specify the column operation to be performed and the subrow to be activated.