Digital Delay Oscillator for On-Chip Temperature Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In modern system-on-a-chip (SoC) implementations, especially in 2.5D or 3D integrated circuits, thermal management is challenging due to hot spots and the inefficiency of existing thermal diode-based temperature sensing methods, which are bulky and interfere with digital circuits, making it difficult to accurately monitor temperature within the chip.
Innovation Solution
A digital circuit comprising a temperature sensor and an oscillator that uses a diode-connected transistor and current source to generate a temperature-sensitive voltage, eliminating the need for an analog-to-digital converter and allowing accurate temperature sensing within digital devices like CPUs and GPUs, with a compact and area-efficient design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional thermal diode-based temperature sensing is used, then temperature monitoring is achieved, but the device occupies large area and interferes with digital circuits
Solution Approach 1:
The patent replaces the mechanical/analog thermal diode sensing system with a digital temperature sensing system that uses a diode-connected transistor and digital logic circuitry. This substitution eliminates the need for bulky analog components and their associated analog-to-digital converters, achieving compact integration while maintaining temperature measurement capability.
Solution Approach 2:
The patent merges the temperature sensing function directly into the digital circuit fabric by using a diode-connected transistor that shares nodes with existing digital logic (such as NOR gates). This integration eliminates separate sensing components and reduces overall sensor area by combining multiple functions into unified circuit structures.
2Measurement precision
If traditional thermal diode-based temperature sensing is used, then temperature monitoring is achieved, but it interferes with digital circuits
Solution Approach 1:
The patent replaces the analog thermal diode system with a fully digital temperature sensing implementation using diode-connected transistors and digital logic gates. This substitution eliminates analog signal paths that are susceptible to interference and coupling issues with digital circuits, achieving immune temperature sensing within the digital domain.
Solution Approach 2:
The patent introduces diode-connected transistors as intermediary elements that sense temperature effects (threshold voltage variations) and convert them into digital-signal-compatible voltage changes. These transistors act as mediators between the physical temperature parameter and the digital logic system, enabling accurate sensing without direct interference with digital circuit operation.
3Measurement precision
If analog-to-digital converter is used for temperature sensing, then temperature measurement is achieved, but device complexity and area increase
Solution Approach 1:
The patent replaces the complex analog-to-digital conversion process with a direct digital sensing approach using diode-connected transistors whose voltage characteristics change with temperature. This substitution eliminates the need for separate ADC circuitry and calibration mechanisms, achieving temperature measurement through inherently digital voltage comparisons that reduce overall system complexity.
4Productivity
If high gate count and high operating frequency are used in SoC, then circuit performance is improved, but heat dissipation and thermal management become more challenging
Solution Approach 1:
The patent implements self-service thermal management by integrating temperature sensing capability directly into the high-performance digital circuit fabric. The diode-connected transistors continuously monitor temperature conditions generated by high gate count and operating frequency, enabling real-time thermal awareness without external monitoring systems, allowing the circuit to self-regulate or trigger cooling mechanisms when needed.
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 solution provides accurate and efficient temperature sensing within digital devices, enabling effective thermal management by leveraging a linear relationship between oscillation frequency and temperature, thus improving the monitoring of hot spots without the size and interference issues of traditional thermal diodes.
Implementation Method 1
A digital circuit includes a temperature sensor and an oscillator. The temperature sensor provides a temperature-sensitive voltage
Implementation Method 2
The oscillator includes a digital delay cell and an adjustment device. The adjustment device adjusts, based on the temperature-sensitive voltage, a delay of the digital delay cell, wherein the digital delay cell produces, based on the adjusted delay, a signal at an oscillation frequency
Data Source
AI summary
A device includes a sensor and an oscillator. The sensor provides a temperature-sensitive voltage. The oscillator includes a digital delay cell and an adjustment device. The adjustment device, based on the temperature-sensitive voltage, adjusts a delay of the digital delay cell, wherein the digital delay cell produces, based on the adjusted delay, a signal at an oscillation frequency.