Memory Device Refresh Cycle Calculation Using Temperature Slopes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The complexity of controlling refresh cycles in dynamic random access memory (DRAM) devices due to the large amount of data required for efficient data retention, especially at varying operating temperatures, leads to inefficiencies in refresh current consumption and storage capacity usage.
Innovation Solution
A memory device that calculates an operating cycle for refresh operations based on the operating temperature using temperature-slope data, integrating slope values to determine the optimal refresh cycle, thereby reducing the amount of data needed for storage and improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the DRAM performs frequent refresh operations to maintain data retention, then data retention is improved, but refresh current consumption increases
Solution Approach 1:
The patent applies dynamics by making the refresh cycle adaptive rather than fixed. The cycle calculating circuit dynamically adjusts the refresh cycle length based on the operating temperature, using longer cycles at lower temperatures and shorter cycles at higher temperatures. This dynamic adjustment optimizes the balance between data retention and refresh current consumption under varying thermal conditions.
Solution Approach 2:
The patent changes the parameter of refresh cycle length based on operating temperature. The cycle calculating circuit uses temperature-slope data to determine appropriate cycle lengths, effectively changing the refresh operation parameter according to environmental conditions. This allows the system to maintain data retention while minimizing unnecessary refresh operations at lower temperatures.
2Productivity
If the DRAM stores temperature-slope data for accurate refresh cycle calculation, then refresh operation efficiency is improved, but storage capacity requirement increases
Solution Approach 1:
The patent segments the temperature range into multiple discrete levels, each associated with specific slope values. Instead of storing comprehensive continuous temperature-cycle data, the system stores discrete temperature-slope pairs in lookup tables. This segmentation reduces the quantity of stored data while maintaining sufficient accuracy for efficient refresh cycle calculation across different operating conditions.
Solution Approach 2:
The patent uses simplified slope value representations rather than storing complete temperature-cycle characteristics. By copying only the essential slope information and using lookup tables, the system reduces storage requirements while preserving the ability to calculate accurate refresh cycles. The cycle calculating circuit retrieves pre-computed slope values for different temperature ranges, avoiding the need to store and process extensive temperature-dependent data.
Data Source
AI summary
A memory device may include a cell array and a cycle calculating circuit. The cycle calculating circuit may calculate an operating cycle of a refresh operation to be performed at the cell array, based on an operating temperature of the memory device. In response to the operating temperature being lower than a first temperature, the cycle calculating circuit may be configured to calculate the operating cycle by integrating one or more slope values of a second slope value to an nth slope value that are arranged from a highest temperature to a lowest temperature. The second slope value may correspond to a second temperature, the nth slope value may correspond to an nth temperature, n may be a natural number of 2 or more, and a number of the one or more slope values may be based on the operating temperature.