Mechanically Attached Edge Shield for PCB

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Tighter packaging requirements in mobile devices lead to challenges in minimizing the footprint of shield cans on printed circuit boards (PCBs) while effectively shielding sensitive electronic components from interference, as soldered connections occupy valuable space and obscure component visibility.

Innovation Solution

A printed circuit board design featuring a plated edge surface and a shield wall that form a continuous conductive loop, with a shield lid mechanically engaged and in conductive contact, reducing the top surface area occupied by the shield and allowing for better component inspection and interference protection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If soldered shield cans are used to shield sensitive electronic components, then shielding effectiveness is improved, but PCB space is consumed due to perimeter flange requirements

Engineering Contradiction:

Improveelectronic interferenceVSAvoidPCB space

Core Design Contradiction:

Object-affected harmful factorsVSArea of stationary object

Solution Approach 1:

The shield can is merged with the PCB edge by eliminating the perimeter flange and using the plated edge surface as part of the shielding structure. The shield wall extends from the PCB edge, integrating the shield with the board structure itself, thereby reducing the overall footprint while maintaining shielding effectiveness.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The shielding approach transitions from a two-dimensional soldered flange connection to a three-dimensional structure where the shield wall extends vertically from the PCB edge. This dimensional change allows the shield to provide effective protection without occupying additional horizontal PCB space.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Area of stationary object

If solder overprint is used to reduce shield footprint, then PCB space is freed up, but manufacturing complexity increases due to solder wicking requirements

Engineering Contradiction:

ImprovePCB spaceVSAvoidshield assembly

Core Design Contradiction:

Area of stationary objectVSEase of manufacture

Solution Approach 1:

The complex solder overprint process is extracted and replaced with a simpler mechanical attachment method. The shield lid is mechanically attached to the shield wall using tabs and slots, eliminating the need for solder wicking and reducing manufacturing complexity while maintaining the reduced footprint benefit.

Inventive Principle:

Principle #2Taking out (Extraction)

3Strength

If soldered connections are used for shield attachment, then mechanical strength is improved, but space consumption and component visibility are reduced

Engineering Contradiction:

Improveshield connectionVSAvoidPCB space

Core Design Contradiction:

StrengthVSArea of stationary object

Solution Approach 1:

The shield attachment is segmented into multiple attachment points distributed along the shield wall rather than requiring a continuous perimeter flange. This segmentation allows the shield to be securely attached with minimal PCB space occupation, while the mechanical tabs and slots provide sufficient connection strength.

Inventive Principle:

Principle #1Segmentation

4Reliability

If perimeter flange is included for soldered connection, then connection reliability is improved, but shield footprint increases

Engineering Contradiction:

Improvesoldered connectionVSAvoidshield footprint

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The soldered mechanical connection system is replaced with a purely mechanical attachment system using tabs, slots, and friction fit. This substitution eliminates the need for a large perimeter flange while maintaining connection reliability through precise mechanical interlocking features.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 minimizes PCB size by freeing up space for component placement, enhances shielding effectiveness, and facilitates easier inspection of electronic components, addressing the issues of space efficiency and interference protection.

Implementation Method 1

One solution is encompassing the sensitive electronic components within one or more shield cans (e.g., a physical enclosure operated as a faraday cage) soldered to the PCB.

Methodology Applied

Scientific EffectFaraday cage: Faraday Cage

Implementation Method 2

The plated edge surface and the shield wall form a continuous conductive loop.

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS10375865B2Mechanically attached edge shield

Publication Date: 2019.08.06 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

The edge shields disclosed herein utilize a plated edge surface of a PCB to form one or more sides of an electronic shield to reduce the amount of top surface area of the PCB occupied by the electronic shield. More specifically, an edge shield lid is mechanically attached to the plated edge surface to remove a need for solder overprint at the edge of the PCB. The edge shield lid is soldered, welded, adhered, or mechanically attached to edge walls where there is no available edge surface for attachment.