Ultra -Low Power VLSI Circuit Design Using Sub-Threshold Techniques for Efficient Internet of Thing Devices

Abstract

The invention provides a transformative approach to VLSI circuit design for IoT, enabling energy-efficient and reliable operation under stringent power constraints.

Specification

Description:Field of Invention:
The present invention relates to ultra-low power Very-Large-Scale Integration (VLSI) circuit design, particularly to the use of sub-threshold operation techniques for designing energy-efficient devices for Internet of Things (IoT) applications.
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Background of the Invention:
The proliferation of IoT devices demands highly energy-efficient circuits due to the limited power sources, often relying on batteries or energy harvesting. Conventional VLSI design techniques operating in super-threshold regions incur high power consumption, making them unsuitable for such applications. Sub-threshold techniques, where transistors operate below their threshold voltage, offer significant power savings but face challenges such as reduced performance, increased sensitivity to noise, and variability.
This invention addresses these challenges by proposing a novel methodology and design framework that combines sub-threshold operation with adaptive biasing, dynamic threshold tuning, and error correction mechanisms, ensuring reliability, scalability, and energy efficiency.
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Summary of the Invention:
The invention provides a VLSI design framework tailored for ultra-low power IoT applications. Key features include:
1. Sub-Threshold Operation: Transistors operate in the sub-threshold region to minimize leakage and dynamic power consumption.
2. Adaptive Body Biasing: Dynamic adjustment of body bias voltages to optimize performance and mitigate variability.
3. Threshold Voltage Tuning: Utilizes dynamic threshold adjustment to enhance reliability under varying operational conditions.
4. Error Compensation Techniques: Implemented to correct errors arising from sub-threshold operation, ensuring data integrity.
5. Energy Harvesting Compatibility: Integrated circuits are optimized for compatibility with energy harvesting systems to extend device life.
6. Hierarchical Clocking Mechanism: Low-power clocking strategies tailored for sub-threshold operation.
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Detailed Description of the Invention:
1. Sub-Threshold Operation:
The invention leverages the exponential dependence of sub-threshold current (IdsI_{ds}Ids) on gate-to-source voltage (VgsV_{gs}Vgs) to achieve ultra-low power consumption. The circuits are designed to operate at voltages below the transistor threshold voltage (VthV_{th}Vth).
2. Novel Circuit Architectures:
• Low-Leakage Logic Gates: Gates designed to minimize leakage current using high-VthV_{th}Vth transistors.
• Level Shifters: Efficient level shifters to bridge sub-threshold and super-threshold domains.
• Memory Circuits: SRAM cells optimized for sub-threshold operation with stability enhancements.
3. Adaptive Body Biasing (ABB):
Dynamic adjustment of body bias is used to control VthV_{th}Vth, enabling compensation for process variations and ensuring consistent performance.
4. Dynamic Threshold Tuning:
• Utilizes on-chip sensors to monitor environmental conditions (temperature, supply voltage) and dynamically adjusts threshold voltages.
• Includes a feedback loop to optimize VthV_{th}Vth for minimal energy consumption without sacrificing reliability.
5. Error Compensation Mechanisms:
• Redundant Computing Units: Hardware redundancy for error detection and correction.
• Error Prediction Algorithms: Predicts potential failures in real-time and adjusts operating parameters.
6. Energy Harvesting Compatibility:
Circuits are designed to operate efficiently with input power variations typical of energy harvesting sources.
7. Hierarchical Clocking:
A multi-level clocking scheme is proposed to further reduce dynamic power consumption.
, Claims:Claims:
1. A VLSI circuit design methodology leveraging sub-threshold operation for ultra-low power consumption in IoT devices.
2. A system for adaptive body biasing, dynamically adjusting body bias voltage to optimize performance.
3. A method for threshold voltage tuning, adjusting the transistor threshold voltage in response to environmental conditions.
4. An error correction mechanism integrated into sub-threshold circuits to maintain operational reliability.
5. A low-leakage SRAM design specifically optimized for sub-threshold operation.

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