Ferroelectric Memory Circuit Initialization Using In-Phase AC Bit Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing semiconductor circuits with ferroelectric capacitors face challenges in performing initialization operations quickly and efficiently, which are necessary to improve ferroelectric characteristics and ensure stable data storage.
Innovation Solution
A semiconductor circuit design incorporating first and second inverters, storage circuits, power supply switches, and transistors, with specific driving operations to apply alternating-current signals to bit lines, enabling rapid initialization of ferroelectric storage elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an initialization operation is performed on ferroelectric storage elements, then ferroelectric characteristics are improved and stable data storage is achieved, but the operation time increases
Solution Approach 1:
The patent applies periodic alternating-current signals to the bit lines during initialization operation. By using periodic AC signals instead of continuous signals, the ferroelectric capacitor is subjected to repeated polarization switching cycles that effectively improve ferroelectric characteristics while maintaining reasonable operation time. The periodic nature of the signals enables efficient initialization without requiring excessively long durations.
2Use of energy by moving object
If power supply is stopped to reduce power consumption, then power gating is achieved, but the circuit cannot perform normal operations
Solution Approach 1:
The patent performs preliminary data transfer from the volatile SRAM to the nonvolatile ferroelectric storage elements before stopping power supply. This preliminary action ensures that critical data is preserved in the nonvolatile memory, allowing the circuit to be powered down for energy savings while maintaining data availability for future operations. When power is restored, the circuit can quickly resume operations using the preserved data.
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
The design allows for rapid improvement of ferroelectric characteristics, enabling stable data storage and quick restoration of operation states after power resumption, reducing power consumption through power gating.
Implementation Method 1
a nonvolatile storage element using a ferroelectric capacitor
Implementation Method 2
an initialization operation is performed in which an alternating-current signal is applied to the storage element before shipment. Ferroelectric characteristics of the storage element are improved by the initialization operation
Data Source
AI summary
A semiconductor circuit according to the present disclosure includes: first and second inverters coupled to first and second power supply nodes, a first control line, a first storage circuit, first and second power supply switches, first and second bit lines, a first word line, first and second transistors each having a gate coupled to the first word line, and a driving section that is configured to perform a first driving operation and a second driving operation. In the first driving operation, in a period in which the first and second power supply switches are turned on, the first word line is set active, and signals having logic levels different from each other are applied to the respective first and second bit lines. In the second driving operation, in a period in which the first and second power supply switches are turned off, the first word line is set active, and a first alternating-current signal and a second alternating-current signal are respectively applied to the first and second bit lines. The first alternating-current signal and the second alternating-current signal are signals in phase with each other.