Inductive Coil Structures for Parallel Bus Cross Talk Cancellation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

High-speed parallel bus designs face challenges in mitigating cross talk due to dense routings and vertical transitions on circuit boards, leading to channel loss, impedance discontinuity, and inter-symbol interference (ISI).

Innovation Solution

The implementation of a passive, coupled inductive coil structure on the die, which mitigates inductive cross talk by optimizing coil winding direction to create a neutralizing coupled signal, thereby reducing far-end cross talk (FEXT) and equalizing channel response.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If dense routings and vertical transitions are used on circuit boards to achieve high-speed parallel bus designs, then signal transmission speed is improved, but cross talk effects worsen

Engineering Contradiction:

Improvesignal transmission speedVSAvoidcross talk effects

Core Design Contradiction:

SpeedVSObject-affected harmful factors

Solution Approach 1:

The patent introduces inductive coupling structures that deliberately create controlled inductive effects to counteract unwanted cross talk. By using coupled inductive coils or vias that generate opposing magnetic fields, the design converts the harmful inductive coupling into a beneficial cancellation mechanism, reducing far-end cross talk (FEXT) while maintaining high-speed signal transmission

Inventive Principle:

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

Solution Approach 2:

The patent modifies physical parameters such as the number of inductive coupling structures, their spacing, winding directions, and connection configurations to optimize cross talk cancellation. By adjusting these parameters, the system achieves reduced FEXT and improved signal integrity without sacrificing transmission speed or increasing overall system complexity

Inventive Principle:

Principle #35Parameter changes

2Reliability

If inductive coupling structures are added to reduce cross talk, then signal integrity is improved, but device complexity increases

Engineering Contradiction:

Improvesignal integrityVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The inductive coupling structures are designed to automatically generate compensating signals in response to transmitted signals. The coupled coils or vias inherently create opposing magnetic fields that cancel cross talk without requiring external control circuits, active components, or complex feedback mechanisms, thus maintaining signal integrity while avoiding additional complexity

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent integrates inductive coupling structures directly into existing bus lines, trace layers, or via configurations. By merging the cross talk cancellation function with the existing signal transmission path and using the same conductive elements for multiple purposes, the design achieves signal integrity improvement without adding separate complex subsystems

Inventive Principle:

Principle #5Merging (Combining)

3Loss of energy

If inductive coupling structures are implemented to mitigate cross talk, then channel loss is reduced, but manufacturing complexity increases

Engineering Contradiction:

Improvechannel lossVSAvoidmanufacturing complexity

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The inductive coupling structures utilize standard PCB materials such as copper traces, via holes, and conventional coil geometries that can be manufactured using existing PCB fabrication processes. By avoiding specialized components and using readily available materials and techniques, the patent reduces channel loss without significantly increasing manufacturing complexity or cost

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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 solution effectively reduces FEXT, minimizes channel distortion, and improves signal integrity, enabling cost-effective platform solutions for high-performance, small form factor systems with reduced motherboard size and layer count.

Implementation Method 1

a first inductive coil coupled to the first trace; and a second inductive coil coupled to the second trace, wherein the first and second inductive coils are arranged to inductively couple with one another

Methodology Applied

Scientific EffectElectromagnetic Induction: Electromagnetic Induction

Data Source

PatentUS12336088B2Inductive coupling structures for reducing cross talk effects in parallel bus technologies

Publication Date: 2025.06.17 INTEL CORP

AI summary

In one embodiment, an apparatus includes a circuit board having a parallel bus with a first trace and a second trace, a first inductive coil coupled to the first trace, and a second inductive coil coupled to the second trace. The first and second inductive coils are arranged to inductively couple with one another to reduce cross talk effects in the parallel bus.