Card Edge Connector Geometry for Low Crosstalk Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-density electrical connectors face challenges in reducing crosstalk, especially at high frequencies, due to electromagnetic coupling between conductors, which affects signal fidelity and noise ratio, and existing designs struggle to precisely control crosstalk while maintaining mechanical and electrical requirements.
Innovation Solution
The design incorporates specific conductor configurations, including differential signal pairs with uniform spacing, tapered tip portions, and overmolding with openings to expose conductors to air, reducing electromagnetic coupling and crosstalk by adjusting the size and shape of conductors and the material in contact with them.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the pitch between adjacent electrical contacts is reduced to increase conductor density, then the number of circuits per area increases, but electromagnetic coupling between conductors increases causing higher crosstalk
Solution Approach 1:
The patent applies local quality by creating non-uniform conductor geometry along their length. Specifically, the conductors have different widths at different positions: wider at the contact portion and narrower at the tip portion. This local variation in conductor dimensions allows optimization of signal integrity at the contact interface while reducing electromagnetic coupling in the midsection, thereby reducing crosstalk in high-density configurations.
Solution Approach 2:
The patent changes physical parameters of the conductors, specifically the width parameter, to optimize performance. By varying the conductor width along its length (wider contact portion transitioning to narrower tip portion), the patent adjusts the electromagnetic field distribution and impedance characteristics. This parameter change enables reduced crosstalk while maintaining effective signal transmission in high-density connector designs.
2Reliability
If ground conductors are placed adjacent to signal conductors to control impedance and reduce crosstalk, then signal integrity improves, but the connector complexity and manufacturing difficulty increase
Solution Approach 1:
The patent merges multiple functions into the signal conductors themselves. The conductors serve both as signal transmission paths and as their own grounding/reference structures through their geometric design. The non-uniform width creates natural impedance control and electromagnetic field containment without requiring separate ground conductors adjacent to each signal pair, thereby reducing structural complexity while maintaining signal integrity.
Solution Approach 2:
The conductors are designed to perform multiple functions simultaneously: signal transmission, impedance control, and crosstalk reduction. The varying width profile enables each conductor to act as both a signal carrier and an electromagnetic shield for adjacent conductors, eliminating the need for dedicated ground conductors and simplifying the overall connector structure.
3Strength
If conductor width is increased to improve contact force and mechanical robustness, then mechanical strength improves, but the area occupied by each conductor increases reducing the number of circuits per area
Solution Approach 1:
The patent segments the conductor width into different sections along its length. The contact portion has a wider width to provide sufficient mechanical strength and contact force, while the tip portion has a narrower width to reduce electromagnetic coupling. This segmentation allows each section to be optimized for its specific function without compromising the other, enabling high-density configurations with adequate mechanical robustness.
Solution Approach 2:
The patent resolves the conflict by transitioning from a uniform two-dimensional cross-section to a three-dimensional varying cross-section along the conductor length. By making the conductor width a function of position rather than a constant parameter, the design accommodates both wide contact portions for mechanical strength and narrow tip portions for reduced crosstalk, effectively packing more circuits per area while maintaining contact force.
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 effectively reduces crosstalk resonances, improves signal integrity, and meets the requirements for high-frequency signals, such as those above 20 GHz, while maintaining mechanical robustness and contact force.
Implementation Method 1
electromagnetic coupling between conductors, which affects signal fidelity and noise ratio
Data Source
AI summary
An electrical connector includes a first set of conductors, a first overmolding in physical contact with a body portion of each of the first set of conductors, a second set of conductors, a second overmolding in physical contact with the body portion of each of the second set of conductors, and a spacer in contact with the first overmolding and the second overmolding. A gap is present between the spacer and at least one of the first set of conductors and a gap between the spacer and at least one of the second set of conductors.