Page 10 - Power & Data Connectivity Expand Electronic Capabilities eBook

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Crosstalk reduction can be obtained with good segregation between each way. However, this is not completely possible with commercial connectors such as D-sub, Micro-D, and D-38999 connectors. Adapted cable and connectors are required to guarantee segregation for the whole link.
Eyes wide open!
Matched impedance, skew, and losses all contribute to signal integrity. By providing better signal integrity, the cable assembly terminated with adapted connectors can reach far higher data rates. Cable length also plays a role on the signal quality — the longer the cable, the worse the signal.
The Eye Diagram (or Eye Pattern) is used to visualize signal quality. The name of this measurement comes from the fact that the signals are displayed in the shape of a human eye. It is created by superimposing successive waveforms to create a composite image. The eye pattern shows, on a bit time only, the filtering effects of the electrical signal through the cable such as distortion, reflections, and losses. The wider the eye, the better the signal integrity.
» 3D printing is becoming the dominant manufacturing process to fabricate low-volume specialty shells, including those which specify alternative materials.
How to reduce EMI in high data rate links
» A comparison of shielding effectiveness between an optimized MicroMach connector and a non-optimized connector.
Cable screen is the best way to minimize electromagnetic interference on a signal line and guarantee good signal integrity for high data rate links. Screening is a conductive layer on wire/cable insulation. The conductive layer can be made with a stranded silver copper braid only or reinforced with a conductive foil. Cable screen termination to connector plays a major role in reducing EMI in a harness. If the termination is not correctly achieved, the whole shielding is jeopardized. The technical challenge is to guarantee the best possible junction between cable screen and connector shell. Backshells, which are usually used to fulfill this function, must be properly connected to the connector shell. Simulation tools are useful to optimize the EMC performance by taking into account parameters including weight and shield
coverage.