Double-Sided PCB Current Sensor for Sensitivity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current current sensor systems face challenges with high production costs and limited sensitivity due to inductive effects, particularly when using leadframes and single-sided current conductor configurations.
Innovation Solution
Implementing a double-sided current conductor configuration on a printed circuit board with conductive vias connecting the conductors, allowing the magnetic field sensor to detect a stronger magnetic field, thereby increasing sensitivity, and embedding the sensor and interface within the PCB for galvanic isolation and reduced production effort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a single-sided current conductor configuration is used, then the production cost is reduced and the structure is simplified, but the magnetic field strength and sensitivity are limited
Solution Approach 1:
The patent transitions from a single-sided (2D) current conductor configuration to a double-sided (3D) configuration, placing current conductors on both the front and back sides of the PCB. This dimensional expansion creates a more voluminous magnetic field generation structure, significantly enhancing the magnetic field strength at the sensor location while maintaining standard PCB manufacturing processes
Solution Approach 2:
The patent embeds the magnetic field sensor and sensor interface directly within the PCB structure, nesting these components inside the existing PCB architecture. This integration allows the sensor to be positioned optimally within the magnetic field generated by the double-sided current conductors, maximizing sensitivity while using standard PCB fabrication techniques
2Device complexity
If leadframes are used as current conductors, then the structure is simple, but the sensitivity is limited due to inductive effects and material costs are high
Solution Approach 1:
The patent replaces the traditional leadframe mechanical structure with PCB-trace-based current conductors. This substitution eliminates the inductive effects associated with leadframe geometry and material properties, while leveraging the planar, controlled-impedance transmission line characteristics of PCB traces to generate a more effective magnetic field for sensing
Solution Approach 2:
The patent changes the geometric parameters of the current conductors by extending them beyond the immediate sensor area and optimizing their trace width, length, and routing patterns on the PCB. These parameter optimizations maximize the magnetic field coupling to the sensor while minimizing parasitic inductance, achieving superior sensitivity compared to leadframe implementations
3Measurement precision
If the magnetic field sensor is placed close to the current conductor, then the magnetic field strength is sufficient, but galvanic isolation becomes challenging
Solution Approach 1:
The patent introduces the PCB substrate as an intermediary barrier between the high-current current conductors and the sensitive magnetic field sensor. The PCB's dielectric material provides natural galvanic isolation, allowing the sensor to be positioned close to the current conductors for maximum magnetic field coupling while maintaining electrical isolation through the PCB layers
Solution Approach 2:
The patent embeds the magnetic field sensor within the PCB structure, nesting it between different PCB layers. This embedding provides inherent galvanic isolation through the PCB's layered construction, allowing the sensor to be positioned optimally close to the current conductors while the PCB substrate acts as a galvanic barrier, eliminating the need for additional isolation components
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 approach enhances sensitivity and reduces production costs by creating a stronger magnetic field signal and maintaining a standard package form factor while ensuring galvanic isolation and electromagnetic interference shielding.
Implementation Method 1
magnetic field sensors like Hall sensors are widely used. Such magnetic field sensors sense the magnetic field generated by a current flowing through a current conductor and provide a measurement signal proportional to the intensity of the current
Implementation Method 2
The first and the second current conductor are electrically connected by means of at least one conductive via through the printed circuit board, such that a current path is formed between the first current terminal and the second current terminal
Data Source
Figure 1A~2
Figure 3A~3C
Figure 4~5
AI summary
An integrated current sensor system comprises a printed circuit board (CB) with a magnetic field sensor (MS) with a sensor interface (SI). The printed circuit board (CB) has a first side on which, isolated from the printed circuit board, a first current conductor is arranged with a longitudinal edge of a portion of the first current conductor being proximate to a sensitive area of sensor (MS). The circuit board (CB) has a second side on which a second current conductor (CC2) is, isolated from the printed circuit board (CB), arranged, wherein a longitudinal edge of a portion of the second current conductor (CC2) is arranged proximate to the sensitive area. The first and the second current conductor (CC1, CC2) are electrically connected by means of at least one conductive via (PV).