PCB Through-Hole Layout With Virtual Holes to Prevent Solder Bridging

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The issue of solder bridging between pins during wave soldering of PCBs, particularly when pin spacing is less than 2 mm, is challenging due to excessive heat dissipation and solder application, which is exacerbated by unreasonable device and PCB design, leading to poor soldering outcomes.

Innovation Solution

A wave soldering device with a substrate design featuring pad through-holes and smaller virtual holes connected by lines, where virtual holes are positioned to accommodate excess solder, reducing bridging by directing it away from pad through-holes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If pin spacing is reduced to increase device integration, then device density is improved, but solder bridging between pins occurs due to excessive heat dissipation and solder application

Engineering Contradiction:

Improvedevice densityVSAvoidsoldering quality

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The invention extracts the excess solder from the problematic area (between closely spaced pins) by introducing virtual holes that act as solder sinks. The virtual holes are positioned to receive and contain the excess solder that would otherwise cause bridging, thereby separating the solder flow path from the pin spacing area and enabling closer pin placement without compromising soldering quality.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The virtual holes serve as intermediary structures between the pad through-holes and the solder wave. These virtual holes mediate the solder flow by providing a controlled path for excess solder to redirect into, preventing direct contact between solder and closely spaced pins. The connecting lines act as intermediaries to guide solder flow from pad through-holes to virtual holes.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of manufacture

If unreasonable device and PCB design is used, then manufacturing complexity is reduced, but heat dissipation becomes excessive causing solder bridging

Engineering Contradiction:

Improvedevice design simplicityVSAvoidheat dissipation

Core Design Contradiction:

Ease of manufactureVSTemperature

Solution Approach 1:

The invention applies local quality by creating specific thermal management features at critical locations. The virtual holes are strategically positioned near pad through-holes with closely spaced pins to locally address heat dissipation issues. The connecting lines provide localized thermal pathways that allow controlled heat distribution, preventing excessive heat accumulation at specific pin locations while maintaining overall design simplicity.

Inventive Principle:

Principle #3Local quality

3Quantity of substance

If too much solder is applied to ensure adequate filling, then solder volume is increased, but solder separation becomes difficult causing bridging

Engineering Contradiction:

Improvesolder volumeVSAvoidsolder separation

Core Design Contradiction:

Quantity of substanceVSEase of operation

Solution Approach 1:

The invention converts the harmful effect of excess solder (which causes bridging) into a beneficial feature by providing virtual holes as designated receptacles for the extra solder. The virtual holes, connected via connecting lines, transform the problematic solder overflow into a controlled feature that prevents bridging. The excess solder is redirected into virtual holes where it serves as a visual indicator of proper solder flow rather than causing defects.

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 design effectively prevents solder bridging, enhances soldering yield, and ensures better soldering quality by allowing excess solder to flow into virtual holes, thus minimizing pin bridging and improving overall soldering efficiency.

Implementation Method 1

a direction from the pad through-hole to the corresponding virtual hole is a second direction, a direction opposite to a direction of the wave soldering device entering a wave soldering equipment is a third direction, an included angle between the second direction and the third direction is less than or equal to 90°

Methodology Applied

Scientific EffectSolder flow direction control:

Data Source

PatentUS20260013050A1Wave soldering device, manufacturing method thereof and printed circuit board

Publication Date: 2026.01.08 INSPUR SUZHOU INTELLIGENT TECH CO LTD

AI summary

A wave soldering device, a manufacturing method thereof and a printed circuit board are provided. The wave soldering device includes: a substrate including a front surface and a back surface opposite to each other; a target hole group including a pad through-hole, a plurality of pad through-holes are provided and distributed at intervals along a first direction, the plurality of pad through-holes penetrate through the front surface and the back surface of the substrate; a virtual hole group including a virtual hole, a plurality of virtual holes are provided, the plurality of virtual holes penetrate through the back surface of the substrate, the plurality of virtual holes are located on the same side of the plurality of pad through-holes in a one-to-one correspondence, a diameter of the virtual hole is less than a diameter of the pad through-hole.