Bridge-Structured Shunt Resistor for Low-TCR Current Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shunt resistors face challenges in minimizing the absolute value of the temperature coefficient of resistance (TCR), which affects current detection accuracy under temperature fluctuations.
Innovation Solution
The shunt resistor design incorporates a bridge structure made of a conductor with a higher resistance than the base structure, coupled to the electrodes via connections. This bridge structure has a smaller size and includes voltage detecting portions and slit portions to optimize resistance and temperature stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional base structure with resistance element and electrodes is used, then the shunt resistor achieves basic current detection function, but the absolute value of temperature coefficient of resistance remains large
Solution Approach 1:
The shunt resistor is divided into two functional segments: a base structure (resistance element and electrodes) and a bridge structure. The bridge structure is further segmented into connection portions and voltage detecting portions. This segmentation allows each part to perform its specific function optimally, with the bridge structure specifically designed to compensate for temperature effects on the base structure.
Solution Approach 2:
The shunt resistor uses a composite structure combining different materials: the base structure uses resistance alloy (such as copper-nickel alloy) for the resistance element and highly conductive metal (such as copper) for electrodes, while the bridge structure uses conductor material with specific resistance properties. This composite approach allows the bridge structure to compensate for temperature coefficient of resistance in the base structure.
2Reliability
If the bridge structure has higher resistance than the base structure at connections, then temperature coefficient of resistance is reduced, but device complexity increases
Solution Approach 1:
The bridge structure merges multiple functions into a single component: it provides electrical connection between electrodes, establishes a higher resistance path for temperature compensation, and includes voltage detecting portions for measurement. The connection portions and voltage detecting portions are integrated into one bridge structure, reducing the need for separate components.
Solution Approach 2:
The bridge structure serves multiple purposes simultaneously: it acts as an electrical connector, a temperature compensation element through its higher resistance, and a platform for voltage detection. This multi-functionality reduces the overall system complexity despite adding structural elements.
3Reliability
If voltage detecting portions are arranged at both end-portion sides of the bridge structure, then temperature compensation is optimized, but manufacturing precision requirements increase
Solution Approach 1:
The bridge structure has different properties in different regions: the connection portions are designed with specific resistance characteristics to connect to electrodes, while the voltage detecting portions are positioned at both ends with specific geometric features. This local differentiation optimizes temperature compensation while providing clear manufacturing guidelines for each region.
Solution Approach 2:
The voltage detecting portions are arranged at both end-portion sides of the bridge structure to create symmetric potential detection points. This symmetric arrangement helps in achieving equipotential conditions that optimize temperature compensation effects and simplify the manufacturing process by providing clear reference points.
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 implementation of the bridge structure in the shunt resistor effectively reduces the absolute value of the temperature coefficient of resistance, enhancing current detection accuracy and stability across varying temperatures.
Implementation Method 1
The bridge structure has a higher resistance than a resistance of the base structure at the connections. The shunt resistor having such a structure can reduce the absolute value of the temperature coefficient of resistance thereof.
Data Source
AI summary
A shunt resistor capable of reducing an absolute value of a temperature coefficient of resistance is disclosed. The shunt resistor includes: a base structure including a resistance element and a pair of electrodes; a bridge structure configured to bridge the pair of electrodes and made of a conductor; and connections configured to couple the pair of electrodes to the bridge structure. The bridge structure has a higher resistance than a resistance of the base structure at the connections.