Page 36 - Power & Data Connectivity Expand Electronic Capabilities eBook

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Reduce line down risk for automatic substrate assembly
High requisites of data and power for on-board electronics result in ever more complex electrical layouts. The number of interconnects required on the PCB substrates are also increasing. To avoid line down and rework costs for automatic substrate assembly, certain connectors, such as floating connectors, have been developed for this specific purpose.
Floating connectors are an effective solution to absorbing alignment errors and cumulative tolerances, thereby increasing production efficiency and cost-effectiveness in automated PCB assembly. The spring-like contacts reduce the stress applied to the mounted parts and enhance the connector’s reliability by preventing solder cracks. These contacts reduce the chance of misalignment and tolerances during the process and in doing so, enhance the design flexibility.
Self-Alignment
Choose your cross-mated components wisely
Cross-mating components is a widely practiced cost-reducing solution. Cross-mating means each side of the connector comes from a different manufacturer. However, on-board electronics are often modules that must be connected to the vehicle mainframe through cable assemblies, which means compatibility of the mating connectors on the module side is of the utmost importance. If connection is lost, all is lost. Therefore, a few considerations must be addressed before deciding which component to use:
1. Tolerance
Tolerance is a range indicating how much a dimension could vary from the nominal measurement. When tolerances of two mating connectors are controlled by separate manufacturers, the risk of compatibility issues increases. This is the first possible cause of quality issues when using cross-mated connectors. Dimension specifications should be diligently communicated during design-in, and the precision capability of the manufacturers must be thoroughly audited.
2. Contact structure and material
A contact system is the main determinant of power and signal integrity. Its structural design has a great influence on the electrical performance which is amplified particularly during high-speed transmission. The contact material acts as the transmission medium which determines the deterioration of electrical transmission. The detail technicality is beyond the scope of this article. However, we suggest thorough design simulations and laboratory analytics to prevent possible failures.
» Floating connector mating during substrate assembly