Memory Circuit Body Bias Switching for Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Semiconductor memory devices face challenges in reducing leakage current while maintaining fast access, high data storage capacity, and low power consumption.
Innovation Solution
A memory device is designed with a body bias generator that applies a reverse body bias voltage to non-operating circuits, increasing the threshold voltage and reducing leakage current by using a function circuit with switches to control body bias voltages for semiconductor devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If reverse body bias voltage is applied to non-operating circuits, then leakage current is reduced, but device complexity increases
Solution Approach 1:
The body bias generator is segmented into multiple output nodes (first node and second node) that can independently control different circuits. The first node provides body bias voltage to reduce leakage in non-operating circuits, while the second node provides supply voltage to operating circuits. This segmentation allows selective application of reverse body bias to specific circuits without affecting the entire device, thus reducing leakage current while limiting the increase in device complexity.
Solution Approach 2:
The patent implements dynamic body bias control by using switches (first switch and second switch) that can dynamically connect or disconnect the body bias voltage based on circuit operating status. The switches enable the body bias generator to adaptively adjust the threshold voltage of transistors in real-time, applying reverse body bias only when needed (in non-operating circuits) and normal supply voltage when circuits are active. This dynamic approach reduces leakage current while avoiding unnecessary complexity in always-on configurations.
2Object-generated harmful factors
If body bias voltage is applied to increase threshold voltage, then leakage current is reduced, but power consumption control becomes more complex
Solution Approach 1:
The body bias generator incorporates feedback control by monitoring the operating status of circuits and adjusting the body bias voltage accordingly. The generator receives control signals that indicate whether circuits are in operating or non-operating states, and automatically applies appropriate voltage levels (reverse body bias for non-operating, normal supply voltage for operating circuits). This feedback mechanism simplifies power consumption control by automating the decision-making process, reducing leakage current in idle circuits without requiring complex manual power management.
Solution Approach 2:
The patent changes the voltage parameter dynamically by switching between different body bias voltage levels. The body bias generator can output different voltage levels (e.g., higher reverse bias voltage for leakage reduction in non-operating circuits, and lower normal supply voltage for operating circuits). This parameter change approach allows flexible control of power consumption across different operating conditions, reducing overall leakage current while maintaining proper power supply to active circuits, thereby simplifying power management complexity.
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 solution effectively minimizes leakage current, enhancing the reliability and performance of semiconductor memory devices by adjusting threshold voltages, thereby reducing data errors and power consumption.
Implementation Method 1
a reverse body bias (RBB) increases the threshold voltage of the transistor
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A memory device for reducing leakage current is provided. The memory device includes a function circuit (300) including a plurality of semiconductor devices (30) and a body bias generator (150) that provides body bias voltages (VBB) to body terminals of the plurality of semiconductor devices (30). The function circuit (300) includes a first circuit (101), a second circuit (102), and first to fourth switches. The first switch (SW1) is connected between the first circuit (101) and a first node (N1) to which the body bias voltage is applied. The second switch (SW3) is connected between the second circuit (102) and a first node (N1). The third switch (SW2) is connected between the first circuit (101) and a second node (N2) to which a supply voltage (VDD) is applied. The fourth switch (SW4) is connected between the second circuit (102) and the second node (N2). The switches (SW1 to SW4) are controlled by a control signal (S_CTRL). The device threshold voltage is increased by the applied body bias voltage (VBB) thereby reducing leakage current.