Shielded Flat Cable Grounding and Reinforcement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Shielded flat cables face challenges in maintaining mechanical strength and reducing characteristic impedance mismatch due to materials with low permittivity exhibiting poor adhesion and uneven grounding of metal foil films, leading to increased radiation noise.
Innovation Solution
A shielded flat cable design with a grounding member extending underneath the terminal, allowing both shield layers to contact the connector ground, leveling noise transmission and improving impedance matching, while a reinforcing plate is firmly bonded to enhance mechanical strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If materials with low permittivity are used as insulating resin film to increase signal frequency, then signal transmission performance is improved, but adhesion to other surfaces deteriorates
Solution Approach 1:
The patent uses a composite structure combining low-permittivity insulating resin film with a reinforcing plate having a magnetic permeability of 1.05 or more. The reinforcing plate is bonded to the insulating resin film to provide mechanical support and improve adhesion without compromising the low-permittivity property needed for high-frequency signal transmission.
2Object-affected harmful factors
If metal foil films are used for shielding, then electromagnetic interference protection is improved, but grounding uniformity deteriorates leading to radiation noise
Solution Approach 1:
The patent changes the magnetic permeability parameter of the reinforcing plate to 1.05 or more, which improves the grounding uniformity of the metal foil films. This parameter adjustment reduces radiation noise while maintaining the electromagnetic interference protection provided by the shield layers.
3Strength
If reinforcing plate is bonded on insulating resin film to improve mechanical strength, then terminal strength is improved, but characteristic impedance mismatch increases
Solution Approach 1:
The patent carefully controls the magnetic permeability parameter of the reinforcing plate (1.05 or more) to minimize its impact on characteristic impedance. This allows the reinforcing plate to provide mechanical strength while maintaining acceptable impedance matching for high-frequency signal transmission.
Data Source
AI summary
A shielded flat cable includes multiple flat conductors arranged in parallel, a lower insulating layer provided on lower surfaces of the multiple conductors, a lower shield layer provided on a lower surface of the lower insulating layer, a lower protective layer provided on a lower surface of the lower shield layer, a lower contact portion that is exposed from the lower protective layer and provided to contact a second contact member of the connector, and that is electrically coupled to the lower shield layer, a terminal in which the multiple conductors are exposed at an end, and a reinforcing plate provided on the lower surface of the lower insulating layer and the lower surfaces of the multiple conductors at the terminal. The multiple conductors extend along the lower insulating layer and the reinforcing plate, and the lower contact portion and the terminal overlap in a side view.