Oscillator Temperature Sensor for Wide-Range Linear Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing temperature sensors fail to provide a substantially linear signal over an extended temperature range of -40°C to 250°C while being compact and low in power consumption, and often require integration with other electronic circuits.
Innovation Solution
A temperature sensor design featuring a controllable current source, oscillator, and control circuit that slaves the equivalent resistance of the oscillator to a reference resistor, using a MOS transistor and operational amplifier to maintain a constant oscillation frequency and linear voltage variation with temperature, along with an analog-digital converter and follower circuit for digital signal processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional temperature sensors are used, then they can measure temperature, but they fail to provide a substantially linear signal over an extended temperature range
Solution Approach 1:
The temperature measurement range is divided into multiple sub-ranges, with each sub-range handled by a dedicated oscillator circuit. Each oscillator is designed to operate optimally within its specific temperature sub-range, ensuring linear signal output. The system segments the overall temperature measurement task into manageable portions, each optimized for linearity within its designated range.
Solution Approach 2:
The patent changes the operating parameters of the oscillator circuits based on temperature conditions. By adjusting the active oscillator among multiple oscillators depending on the current temperature sub-range, the system maintains substantially linear signal output across the extended temperature range. This parameter change approach allows optimal performance in each temperature region.
2Use of energy by moving object
If temperature sensors are made compact and low power, then power consumption is reduced, but integration with other electronic circuits becomes necessary
Solution Approach 1:
The temperature sensor is merged with other electronic circuits to form an integrated system. The oscillator circuits and signal processing components are combined into a single integrated structure, allowing the temperature sensor to benefit from the compactness and low power characteristics of the integrated circuit while maintaining its measurement functionality.
Solution Approach 2:
The integrated circuit structure serves multiple functions: temperature sensing, signal oscillation, analog-to-digital conversion, and output signal generation. By making the device universal and multi-functional, the patent achieves compactness and low power consumption through shared circuitry while still providing accurate temperature measurement capabilities.
3Adaptability or versatility
If multiple oscillators are used to cover extended temperature ranges, then temperature range coverage is improved, but device complexity increases
Solution Approach 1:
The extended temperature range is segmented into multiple sub-ranges, with each oscillator circuit assigned to a specific sub-range. This segmentation allows the system to cover the full temperature range while keeping each individual oscillator circuit relatively simple and optimized for its designated range, rather than requiring one complex oscillator to handle the entire range.
Solution Approach 2:
The system dynamically selects which oscillator circuit to activate based on the current temperature conditions. This dynamic operation allows the system to use only the necessary oscillator for the current temperature sub-range, reducing the effective complexity at any given moment while maintaining comprehensive temperature range coverage through the availability of multiple specialized oscillators.
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 provides a temperature measurement signal that varies linearly with temperature, maintaining stability and reducing power consumption, suitable for applications in drilling, industrial monitoring, and aeronautical engine monitoring, with reduced calibration points and production costs.
Implementation Method 1
a control circuit of the controllable current source configured to slave the equivalent resistance of the oscillator to a reference resistor
Implementation Method 2
the controllable current source comprises a first MOS transistor, the source of which is intended to be connected to a source of a high reference potential, the drain of which supplies the supply voltage to the first node
Implementation Method 3
an operational amplifier whose output is connected to the gates of the first and second MOS transistors
Implementation Method 4
the measurement signal corresponding to the supply voltage... providing a temperature measurement signal that varies linearly with temperature
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The present description relates to a temperature sensor providing a measurement signal (Vosc) varying linearly to within 10% with respect to temperature at least over a temperature range, comprising an oscillator (12) supplied by a supply voltage (Vddosc) and providing a first oscillating signal (Vasc), said oscillator comprising first MOS transistors, the voltage at each internal node of the oscillator (12) having a dynamic range equal to the supply voltage (Vddosc), the measurement signal corresponding to the supply voltage.