Intertwined Coupled-Inductor Low-Pass Filter With Steep Roll-Off
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional low pass filter circuits fail to provide sufficient stop band attenuation in smaller areas and often attenuate lower frequencies undesirably, which is a challenge especially in high-speed wireless communication devices.
Innovation Solution
The use of coupled inductors in conjunction with capacitors on an integrated device, where the inductors are intertwined to enhance stop band attenuation and create additional frequency notches, allowing for a wider stop-band while preserving lower frequencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional low pass filter circuits are used, then the circuit provides basic filtering functionality, but the stop band attenuation is insufficient and the area occupied is larger
Solution Approach 1:
The patent combines multiple inductors into a coupled inductor structure where inductors share common magnetic paths and physical space. This merging of components achieves superior stop band attenuation performance while reducing the overall circuit area compared to conventional separate component layouts
Solution Approach 2:
The coupled inductors are designed with intertwined windings that nest within each other's magnetic fields and physical space. This nested configuration maximizes the use of available space, allowing the filter to achieve enhanced attenuation performance in a compact footprint
2Reliability
If conventional filtering circuits are used, then the circuit structure is simple, but the roll-off from pass band to stop band is not steep enough
Solution Approach 1:
The patent introduces localized coupling between specific inductor windings to create targeted magnetic interaction at critical frequency points. This localized quality enhancement at specific coupling points produces steep roll-off characteristics without requiring complete redesign of the entire filter structure
Solution Approach 2:
The coupled inductor structure creates dynamic magnetic coupling effects that vary with frequency, automatically providing stronger attenuation at stop band frequencies while maintaining pass band performance. This dynamic behavior achieves steep roll-off without additional complex control circuitry
3Adaptability or versatility
If conventional filters are used, then the circuit occupies standard area, but additional frequency attenuation notches cannot be created
Solution Approach 1:
The coupled inductor structure serves multiple functions simultaneously: it provides the primary low pass filtering, creates additional attenuation notches at specific frequencies, and maintains compact size. This multi-functionality allows a single structure to achieve what would traditionally require multiple separate components
Solution Approach 2:
By adjusting the coupling parameters and winding configurations of the coupled inductors, the filter can create attenuation notches at different frequency points. This parameter flexibility allows the same basic structure to be adapted for various frequency requirements without increasing area
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 achieves superior performance with steep roll-off from pass band to stop band, providing significant space savings and improved signal integrity by effectively filtering unwanted signals while allowing desired harmonics to pass through.
Implementation Method 1
coupled inductors are provided along with various capacitors to provide for superior performance within a smaller surface area
Implementation Method 2
the coupled inductors are provided along with various capacitors to provide for superior performance
Data Source
AI summary
The present invention relates to a low pass filter incorporating coupled inductors to enhance stop band attenuation. In one embodiment, the coupled inductors are provided along with various capacitors to provide for superior performance within a smaller surface area of a semiconductor or ceramic integrated device. In a further specific embodiment, the capacitors are formed on an integrated device within an area on which entirely intertwined inductors are formed. In another embodiment, at least one further pair of coupled inductors is included to create additional frequency attenuation notches, as well as a wide stop-band.