3D EMI Suppression Structure for High-Frequency Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional common mode chokes with high magnetic permeability lose effectiveness during high-frequency data transmission, failing to adequately suppress common mode noise in electronic devices, which interferes with wireless communication systems.
Innovation Solution
A 3D EMI suppression structure is implemented in a multilayer substrate, featuring a coplanar waveguide with conducting wire bands and ground parts isolated by grooves, an isolation layer connecting the wire band, and a resonance layer with conductor parts, forming inductive and capacitive effects to suppress common mode noise in differential signal transmission lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a common mode choke with high magnetic permeability is used to suppress common mode noise, then EMI suppression is improved at low frequencies, but the magnetic core loses magnetic permeability at high frequencies, making it ineffective for high-speed data transmission
Solution Approach 1:
The patent changes the suppression mechanism from magnetic permeability-based (frequency-dependent) to geometric resonance-based (frequency-independent). By adjusting the physical dimensions (length and width) of the coplanar waveguide and resonance layer, the structure achieves common mode noise suppression across a broad frequency range including high frequencies, without relying on magnetic material properties that degrade at high frequencies
Solution Approach 2:
The patent replaces the magnetic core-based mechanical filtering system with an electromagnetic resonance-based system using coplanar waveguide structures. This substitution eliminates the frequency limitations of magnetic materials while maintaining effective common mode noise suppression through carefully designed geometric parameters and resonance effects
2Object-affected harmful factors
If conventional shielding or grounding methods are used for radiated EMI, then EMI removal is achieved, but these methods are ineffective for conducted EMI transmitted through power or signal lines
Solution Approach 1:
The coplanar waveguide structure serves multiple functions: it acts as both a transmission line for differential signals and a common mode noise filter. The same structure that guides the desired signal also provides the resonance mechanism for suppressing common mode noise, eliminating the need for separate filtering components and making the solution applicable to both radiated and conducted EMI scenarios
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 structure effectively reduces common mode noise across a specific frequency range, improving signal transmission quality by minimizing electromagnetic interference and maintaining effective suppression during high-speed data transmission.
Implementation Method 1
forming inductive and capacitive effects to suppress common mode noise
Implementation Method 2
forming inductive and capacitive effects to suppress common mode noise
Implementation Method 3
two ground parts positioned at both sides of the conducting wire band and isolated from the conducting wire band by a distance corresponding to a first isolation groove
Data Source
AI summary
A 3D Electromagnetic Interference (EMI) suppression structure and an electronic device having the same, wherein a coplanar waveguide structure, an isolation layer, and a resonance layer may be installed. Furthermore, under the coplanar waveguide structure, the 3D EMI structure may be installed to connect to a conductor part of the resonance layer through a conductive connection part of the isolation layer, thereby further improving the EMI suppression effect and producing an excellent EMI suppression effect.