Variable Resistive Memory Read Noise Reduction via Multi-Voltage Sampling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increasing capacity of resistance change memory devices leads to increased read noise, causing erroneous determination of resistance states, as the reduced read current results in fluctuations that can misinterpret high resistance as low resistance and vice versa.
Innovation Solution
The semiconductor memory device employs a control circuit to apply a read voltage multiple times, comparing determination results to terminate the reading operation when a certain condition is met, and restarts with a different read voltage if conditions are not satisfied, effectively reducing the influence of read noise by executing multiple reading procedures with varying voltages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the capacity of the memory cell array is increased, then the storage density is improved, but the read noise increases causing erroneous determination of resistance states
Solution Approach 1:
The reading operation is segmented into multiple sampling steps (first sampling step and second sampling step) with different read voltages. Instead of determining the resistance state in a single measurement, the patent divides the reading process into multiple discrete sampling operations, each capturing different portions of the read noise profile, thereby improving measurement accuracy in high-capacity memory arrays.
2Use of energy by moving object
If the read current is reduced, then the power consumption is decreased, but the read noise increases causing fluctuations that lead to erroneous determination
Solution Approach 1:
The patent employs periodic action by performing multiple sampling operations at different time points with different read voltages. The reading process is executed periodically with first and second sampling steps, capturing the resistance state under varying conditions. This periodic multi-voltage sampling approach allows accurate determination of resistance states while maintaining low power consumption through reduced individual read currents.
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
This approach reduces the impact of read noise, ensuring accurate determination of resistive states by employing multiple reading procedures with different voltages, thereby minimizing errors due to noise fluctuations.
Implementation Method 1
a resistance change memory device that uses a variable resistive element as a storage element
Implementation Method 2
a control circuit to control a voltage applied to the memory cell. The control circuit applies a read voltage with respect to the memory cell for a plurality of times to determine a resistive state
Data Source
AI summary
A semiconductor memory device according to the embodiments includes a first wiring, a second wiring that extends to intersect with the first wiring, a memory cell that is disposed on each intersection portion of the first wiring and the second wiring, and includes a variable resistive element, and a control circuit to control a voltage applied to the memory cell. The control circuit applies a read voltage with respect to the memory cell for a plurality of times to determine a resistive state of the memory cell for a plurality of times, so as to obtain a first determination result or a second determination result. The control circuit compares the number of the first determination result with the number of the second determination result, terminates a reading operation when the comparison result satisfies a certain condition, and starts the reading operation again when the condition is not satisfied.