Backplane Via Recess Layout for Dense High-Speed Connector Soldering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current interconnection systems face challenges in miniaturization and reliability due to the limitations of press fit and surface mount connectors, particularly in high-speed, high-density applications, where signal density and frequency increase, leading to issues with coplanarity and solder bridging, which affect electrical performance and connectivity.
Innovation Solution
The development of printed circuit boards with conductive elements featuring recesses for solder attachment to surface mount connector leads, allowing for reliable solder connections and reduced area requirements, mitigating the effects of connector lead non-coplanarity and enhancing solder joint reliability through increased surface area and volume.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If press fit connectors are used, then connector reliability is improved, but via diameter must be large which increases area requirements and reduces manufacturing precision
Solution Approach 1:
The patent changes the connection mechanism from mechanical press-fit to solder-based electrical connection. This parameter change allows the via diameter to be significantly reduced while maintaining reliable electrical connectivity through solder joints, thereby improving manufacturing precision without sacrificing connector reliability
Solution Approach 2:
The patent replaces the mechanical press-fit connection system with a solder-based electrical connection system. This substitution eliminates the need for large diameter vias required for mechanical interference fits, allowing smaller, more precisely manufactured vias that are filled with conductive material and connected via solder joints
2Area of stationary object
If surface mount connectors are used, then area requirements are reduced, but solder bridging occurs which worsens manufacturing precision and reliability
Solution Approach 1:
The patent transitions from surface-mounted connector leads to vertically penetrating via structures. By moving the connection interface from the surface plane to the vertical depth dimension, the design allows compact surface footprints while maintaining precise solder joint formation through controlled via geometries that prevent solder bridging
Solution Approach 2:
The patent applies different structural qualities to different parts of the connector system. The surface mount connector leads are positioned to achieve compact area, while the underlying via structures are designed with specific geometries (including recesses and anti-pads) that locally control solder flow and prevent bridging, thus maintaining manufacturing precision throughout
3Reliability
If via diameter is increased to ensure reliable solder connections, then solder joint reliability is improved, but area requirements increase which conflicts with miniaturization goals
Solution Approach 1:
The patent employs curved and tapered via geometries including recesses and anti-pad structures. These curved transitions optimize solder flow paths and distribution, allowing reliable solder joints to form in smaller via diameters by improving solder wetting and reducing void formation, thus achieving both miniaturization and reliability
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 improves the reliability and electrical performance of interconnection systems by ensuring consistent solder connections, reducing the need for large via diameters, and enabling further miniaturization while maintaining high-speed and high-density connectivity.
Implementation Method 1
conductive elements on the upper surface of the backplane for solder attachment to respective connector leads of the surface mount connector
Data Source
AI summary
A printed circuit board includes a plurality of layers including conductive layers separated by dielectric layers; and at least one via configured for solder attachment to a connector lead of a surface mount connector, the at least one via including a conductive element that extends from an upper surface of the printed circuit board through one or more of the plurality of layers, the conductive element having a recess in a surface thereof. The recess is configured to receive a tip portion of the connector lead of the surface mount connector. The printed circuit board may have via patterns including signal vias and ground vias.