Composite Electronic Component Common Mode Noise Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing composite electronic components fail to effectively suppress common mode noise reflection back into differential transmission lines and suffer from degradation of differential signal transmission characteristics due to mismatched impedance and low-frequency signal leakage.
Innovation Solution
A composite electronic component design featuring a common mode filter and differential mode filter with a resistance pattern connected in series between the filters and ground terminals, adjusting the shunt line impedance to match the differential transmission line, and incorporating a capacitor to prevent low-frequency signal transmission, thereby directing common mode noise towards the shunt line and thermally consuming it.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the ground terminal is directly connected to the ground electrode without impedance matching, then the structure is simple, but the common mode noise reflection is not sufficiently suppressed and the shunt line cannot effectively direct noise away from the differential transmission line
Solution Approach 1:
A resistance pattern is introduced as an intermediary element between the second filter (differential mode filter) and the ground terminal. This resistance pattern serves as an impedance matching component that enables the shunt line to effectively absorb and direct common mode noise away from the differential transmission line, resolving the noise reflection issue without requiring complete structural redesign
Solution Approach 2:
The characteristic impedance of the shunt line is adjusted by introducing the resistance pattern, changing the electrical parameter (impedance) to match the differential transmission line's characteristic impedance. This parameter change enables effective common mode noise suppression while maintaining a relatively simple overall structure
2Reliability
If the differential mode filter impedance is reduced in the lower frequency range, then the filter performance improves, but low frequency components of the differential signal leak to the shunt line side causing transmission characteristic degradation
Solution Approach 1:
The resistance pattern in the shunt line, which could potentially cause signal loss, is instead used to create an impedance mismatch that actively prevents low frequency differential signal components from leaking into the shunt line. The resistance converts what would be harmful signal leakage into beneficial signal isolation, while still allowing the differential mode filter to effectively suppress common mode noise
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 design effectively suppresses common mode noise reflection and maintains the transmission characteristic of differential signals by matching impedance and thermally consuming noise, while allowing differential signals to pass through without degradation.
Implementation Method 1
thermally consuming noise
Data Source
AI summary
A composite electronic component includes a main body including insulating layers, first and second input terminals, first and second output terminals, a ground terminal, first and second filters, and a resistance pattern connected between the second filter and the ground terminal. The first filter includes a first coil pattern connected between the first input terminal and the first output terminal, and a second coil pattern connected between the second input terminal and the second output terminal. The first and second coil patterns form a common mode filter. The second filter includes a third coil pattern connected between the first input terminal and the ground terminal, and a fourth coil pattern connected between the second input terminal and the ground terminal. The third and fourth coil pattern form a differential mode filter. The resistance pattern is on the insulating layer different from those of the first to fourth coil patterns.