Electronic Component Shielding Low Frequency Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic components with surface mount devices struggle to effectively reduce or prevent the radiation of low frequency noise, which often escapes through ground conductors and is radiated outside, despite anti-noise measures.
Innovation Solution
The electronic component incorporates a board with a magnetic body layer, a nonmagnetic resin layer, and a metal shield layer, where the surface mount devices are surrounded by a magnetic shield layer and connected via conductors to reduce low frequency noise radiation, and the metal shield layer addresses high frequency noise, with a nonmagnetic intermediate layer enhancing noise shield effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ground terminals of surface mount devices are connected to ground conductors of the base circuit board, then electrical connectivity is established, but low frequency noise propagates to the metal film via the ground conductors and is radiated out
Solution Approach 1:
The shielding structure is segmented into multiple functional layers: a first shielding layer (metal film) connected to ground conductors for high frequency noise, and a second shielding layer (magnetic film) not connected to ground conductors for low frequency noise. This segmentation allows each layer to address specific frequency ranges independently, preventing low frequency noise from propagating through the ground conductor path while maintaining electrical connectivity.
Solution Approach 2:
The magnetic film acts as an intermediary shielding layer between the surface mount devices and the external environment. It mediates the noise protection function by specifically targeting low frequency noise that would otherwise propagate through the ground conductors, while the metal film handles high frequency noise. This intermediary structure prevents low frequency noise radiation without compromising electrical connectivity.
2Object-affected harmful factors
If a single metal film shields the surface mount devices, then high frequency noise is reduced, but low frequency noise passes around and is radiated out
Solution Approach 1:
The shielding function is segmented into two distinct layers with different material properties and grounding configurations. The first shielding layer (metal film) is connected to ground conductors and effectively shields high frequency noise. The second shielding layer (magnetic film) is not connected to ground conductors and specifically addresses low frequency noise. This segmentation resolves the contradiction by assigning different frequency ranges to different shielding mechanisms.
Solution Approach 2:
The shielding structure uses composite material architecture combining a metal film (conductive material) and a magnetic film (magnetic material with different permeability properties). This composite structure leverages the complementary characteristics of different materials: the metal film for high frequency electromagnetic shielding and the magnetic film for low frequency noise attenuation, achieving broad-spectrum noise reduction.
3Object-affected harmful factors
If the metal film covers the entire surface including ground conductors, then high frequency noise is shielded, but low frequency noise with large amplitude flows to ground conductors and is radiated
Solution Approach 1:
The second shielding layer (magnetic film) is selectively applied only to regions where low frequency noise protection is needed, such as areas surrounding ground conductors or specific noise-sensitive components. This local application of magnetic shielding material provides targeted protection against low frequency noise propagation along ground conductor paths without requiring complete coverage, thereby preventing low frequency noise radiation while maintaining high frequency shielding effectiveness.
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 configuration significantly reduces or prevents the radiation of both low and high frequency noise, improving signal transmission efficiency and noise attenuation across a wide frequency band.
Implementation Method 1
since the surface mount device is surrounded by the magnetic shield layer and the magnetic body layer of the board, radiation of low frequency noise that is produced from the surface mount device to the outside is reduced or prevented
Implementation Method 2
Radiation to the outside of low frequency noise that has passed around into the metal shield layer via, for example, a base circuit board on which the electronic component is mounted is also reduced or prevented by the magnetic shield layer. Note that radiation of high frequency noise to the outside is reduced or prevented by the metal shield layer
Data Source
AI summary
An electronic component includes a board, a surface mount device, a nonmagnetic resin layer, a metal shield layer, and a magnetic shield layer. The board includes first and second principal surfaces facing each other, and a magnetic body layer. The surface mount device is mounted on the first principal surface of the board. The nonmagnetic resin layer covers the surface mount device. The metal shield layer covers the nonmagnetic resin layer. The magnetic shield layer covers an entire or substantially an entire surface of the metal shield layer.