Cable Connector Enhancement

It is widely known that the cable to board connection is a common failure prone interface for electronics systems due to the thermal and mechanical stress they are exposed to. For new designs this connection can be engineered such that risk is lowered as much as reasonably possible but for existing design, there are limited options to overcome the difficulty of maintaining a strong reliable electrical connection in stressful environments. Potting PCBA and electronics assemblies offer great moisture, vibration and shock protection but when potting connectors the potting material is limited to the height of the connector below the electrical contact to prevent potting material from disrupting the connection between each end [3]. This ensures the board side of the connector is secure but not the full connection joint. That connection is still easily severed if it is strained beyond its mechanical limits, which for commercial grade connectors are a relatively low threshold. Commercial connectors could be swapped with more specialized connectors if they exist and the pad footprint on the board is still sufficient but removal of existing connectors from PCBAs still require considerable time for technicians. Reworking existing boards for the purpose of swapping the connector adds additional risk of board fallout from damage or thermal cycling. Repeated use of heat guns for removing and replacing a new connector or cable solution can degrade the heat affected zone and reduce reliability of the board and neighboring components. Especially for densely populated boards with limited distance from a connector to neighboring components which may prevent the use of a heat shield due to limited space. A heat shield can typically be used to avoid thermal and mechanical damage to adjacent components on a PCBA [4] Other options have the connector removed entirely in favor of a direct solder connection, be the board to cable or board to board. Alternative joining methods to replace the connector connection such as Hot Bar Soldering (HBS) can be cumbersome in both time and resources for small production efforts for any singular design. HBS uses pulse heated to reflow the solder material between a PCBA and the wire to form a strong junction [1]. The Hot Bar Solder (HBS) process for any given design requires tooling, fixturing and a compatible Anisotropic Conductive Film (ACF); the space between conductors, minimum pad area, the plating and substrates involved. For an existing connector footprint within a design compatible ACF may not exist and may not be able to be sourced in reasonable quantities as ACF is commonly sold by the case. While recent advancement exists for mitigating use of ACF [2] other challenges remain with design the tooling and the rework required to remove existing connectors. The design of the tool shape is critically important to the temperature distribution across the reflow area and has significant impact on the resultant mechanical and electrical properties achieved [1]. Tooling design and fabrication iterations increase schedule requirements for assembly efforts with increasing difficulty for adequate tooling shape on densely populated boards. These different paths or full board redesign and fabrication are expensive, time consuming and limited solutions because they are assembly specific. To enhance prototyping and system integration efforts a more versatile and efficient solution is needed to address this deficiency.