Magnetic Sensor Current Path Initialization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic sensors employing magneto-resistive elements face challenges due to hysteresis in resistance value measurements caused by external magnetic fields, leading to errors and requiring complex structures with high fabrication costs for initialization.
Innovation Solution
A magnetic sensor with a stacked structure of magnetization-free, nonmagnetic, and magnetization-fixed layers, where a current path portion generates a magnetic field by current flow, oriented at an angle to the magneto-resistive element, allowing for efficient initialization and miniaturization with reduced power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a solenoid coil or spiral-shaped coil is used to initialize the magnetization-free layer, then the magnetization can be saturated, but the structure becomes complex and fabrication costs increase
Solution Approach 1:
The patent extracts the initialization function from a separate coil structure and integrates it into the signal line itself. The signal line is configured to carry both the measurement signal and the initialization current, eliminating the need for a dedicated solenoid or spiral coil. This extraction and integration of the initialization function into an existing component resolves the technical contradiction by maintaining magnetization saturation capability while significantly reducing structural complexity.
Solution Approach 2:
The signal line is designed to serve multiple functions: it acts as both the measurement signal transmission path and the initialization magnetization field generation path. By making the signal line multi-functional, the patent eliminates the need for separate initialization coils, thereby reducing device complexity and fabrication costs while maintaining the ability to saturate the magnetization-free layer when needed.
2Reliability
If a solenoid coil or spiral-shaped coil is used to initialize the magnetization-free layer, then the magnetization can be saturated, but the overall shape of the magnetic sensor becomes large
Solution Approach 1:
The patent merges the initialization function with the signal line structure. Instead of having a separate coil that would increase the sensor's footprint, the initialization capability is combined with the existing signal transmission line. This merging of functions allows the sensor to maintain its compact size while still achieving magnetization saturation through the signal line when initialization is required.
3Reliability
If a solenoid coil or spiral-shaped coil is used to initialize the magnetization-free layer, then the magnetization can be saturated, but fabrication costs become high
Solution Approach 1:
The patent extracts the initialization function from a dedicated coil structure and reassigns it to the signal line. This eliminates the need for additional coil fabrication processes, reducing manufacturing steps and associated costs. The signal line, which must already be present for signal transmission, is utilized for dual purposes, thereby simplifying the fabrication process and reducing costs while maintaining magnetization saturation capability.
Solution Approach 2:
By designing the signal line to serve both as a signal transmission path and an initialization magnetization field generation path, the patent reduces the total number of components that need to be fabricated. This multi-functionality approach decreases fabrication complexity and costs, as fewer separate structures need to be created and assembled, while still achieving reliable magnetization saturation 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
The solution enables accurate measurement of external magnetic fields with reduced hysteresis and lower manufacturing costs, achieving a simpler, more compact magnetic sensor design with lower power consumption.
Implementation Method 1
a current path portion which is provided on the magneto-resistive effect element via an insulation layer so as to be spaced apart from the magneto-resistive effect element in the stacking direction, and which generates a magnetic field by being supplied with a current
Implementation Method 2
These magnetic sensors utilize a phenomenon whereby the resistance value of the magneto-resistive effect element depends on the relative angle between the magnetization orientations of a magnetization-free layer and a magnetization fixed layer respectively in the magneto-resistive effect element
Data Source
AI summary
The magnetic sensor according to the present invention includes: a magneto-resistive effect element which has a stacked body in which a magnetization-free layer, a nonmagnetic layer, and a magnetization fixed layer are stacked in this order, and the longitudinal direction of which is a direction perpendicular to the stacking direction; and a current path layer which is provided on the magneto-resistive effect element via an insulation layer so as to be spaced apart from the magneto-resistive effect element in the stacking direction, and which generates a magnetic field by being supplied with a current. The current path layer extends in a direction which forms an angle between 0 and 45 degrees to the longitudinal direction of the magneto-resistive effect element when viewed from the stacking direction.