Electrical Cable Void Shield Design for Signal Skew Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Shielded electrical cables suffer from signal timing skew due to air voids created by overlapping cable shields, which affect the dielectric constant and impair signal performance in high-speed data transmission applications.
Innovation Solution
Incorporating a conductive void shield on the outer surface of the insulator between the conductor assembly and the cable shield, which is aligned with and electrically connected to the cable shield to form an outer electrical shield, thereby eliminating the air void and maintaining uniform shield distance around the conductors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a cable shield is wrapped around the conductor assembly, then electromagnetic interference protection is improved, but air voids are created at the overlap location causing signal timing skew
Solution Approach 1:
A dielectric member is introduced as an intermediary component between the conductors and the cable shield. This dielectric member fills the air void created by the shield overlap, maintaining consistent dielectric properties throughout the cable while preserving the shield's electromagnetic protection function.
Solution Approach 2:
The dielectric constant of the medium surrounding the conductors is changed from air (in the void) to a material with appropriate dielectric properties. This parameter change ensures uniform signal propagation characteristics and eliminates timing skew caused by the air void.
2Reliability
If the cable shield overlaps itself to provide continuous shielding, then shielding effectiveness is improved, but the dielectric constant changes leading to electrical signal timing skew
Solution Approach 1:
The dielectric member acts as a mediator that compensates for the discontinuity introduced by the shield overlap. It fills the resulting void and maintains uniform electrical characteristics, allowing the shield to overlap for continuous coverage without causing signal timing issues.
3Manufacturing precision
If the void shield is positioned interior of the void, then the impact of air voids on signal skew is reduced, but the void shield must be precisely aligned with the void
Solution Approach 1:
The dielectric member is designed with features that enable preliminary positioning and alignment during the cable assembly process. This preliminary action ensures the dielectric member is correctly positioned to fill the void before the shield is installed, reducing the need for complex post-assembly adjustments.
Data Source
AI summary
An electrical cable includes a conductor assembly having conductors and an insulator. The electrical cable includes a cable shield wrapped around the conductor assembly having an inner edge at a first end segment and an outer edge at a second end segment. The second end segment is wrapped over the inner edge and the first end segment to form a flap covering the inner edge and the first end segment. The second end segment forms a void at the inner edge. The electrical cable includes a void shield on the outer surface between the insulator and the cable shield. The void shield extends between a first end and a second end. The void shield is aligned with the void and spans entirely across the void. The cable shield is electrically connected to the void shield.