Multi-Pole Inductor Layout for High Magnetic Isolation

Solution Overview

Problem

Unwanted magnetic coupling between inductors in wireless transceivers degrades performance, particularly as components scale down and are more closely spaced, leading to issues like frequency pulling and increased interference.

Innovation Solution

The use of inductor structures with a conductor path configured such that current flows in opposite directions in adjacent inductors, creating magnetic field loops with opposite polarities, which concentrates magnetic fields around the inductor structure and reduces unwanted coupling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If inductors are scaled down and closely spaced to improve integration density, then device integration is improved, but unwanted magnetic coupling between inductors increases

Engineering Contradiction:

Improveintegration densityVSAvoidmagnetic coupling

Core Design Contradiction:

ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent applies the inversion principle by configuring adjacent inductors to carry currents in opposite directions. This reverses the conventional approach where all inductors carry current in the same direction, and exploits the opposite magnetic field polarities to achieve cancellation of magnetic coupling between adjacent inductors, thereby reducing harmful magnetic interference while maintaining high integration density

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent converts the harmful magnetic coupling effect into a beneficial cancellation mechanism. By strategically arranging inductors with opposite current directions, the magnetic fields that would normally cause interference are transformed into opposing fields that cancel each other out, turning the harmful magnetic interaction into a useful isolation mechanism

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Area of stationary object

If inductors are closely spaced to reduce device area, then area is reduced, but magnetic field interference between inductors increases

Engineering Contradiction:

Improvedevice areaVSAvoidmagnetic field interference

Core Design Contradiction:

Area of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The patent applies the inversion principle by configuring adjacent inductors to carry currents in opposite directions. This reverses the conventional approach where all inductors carry current in the same direction, and exploits the opposite magnetic field polarities to achieve cancellation of magnetic coupling between adjacent inductors, thereby reducing harmful magnetic interference while maintaining high integration density

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent converts the harmful magnetic coupling effect into a beneficial cancellation mechanism. By strategically arranging inductors with opposite current directions, the magnetic fields that would normally cause interference are transformed into opposing fields that cancel each other out, turning the harmful magnetic interaction into a useful isolation mechanism

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 unwanted magnetic coupling between inductor components, improving the performance of transceivers by minimizing interference and allowing for more compact designs.

Implementation Method 1

the conductor path is configured such that, when a current flows from the first terminal to the second terminal, the current flows in a first direction in the first inductor, the third inductor, and the fifth inductor, and the current flows in a second direction in the second inductor, the fourth inductor, and the sixth inductor

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS20240412913A1Multi-pole inductor structures with inherent high isolation

Publication Date: 2024.12.12 QUALCOMM INC

AI summary

An inductor structure has a first terminal and a second terminal, and includes a conductor path between the first terminal and the second terminal. The conductor path includes a first inductor, a second inductor, a third inductor, a fourth inductor, a fifth inductor, and a sixth inductor. The conductor path may be configured such that, when a current flows from the first terminal to the second terminal, the current flows in a first direction in the first inductor, the third inductor, and the fifth inductor, and the current flows in a second direction in the second inductor, the fourth inductor, and the sixth inductor. The first direction may be clockwise and the second direction may be counterclockwise, or vice versa.