paths also reduces the influence of crosstalk.
As mentioned previously, a connector can be influenced by other components of the assembly and also have an electromagnetic effect on surrounding components. With the coupling inductance LK, the connector can be described in both functions – as source and sink. The coupling inductance is to be regarded as an EMC parameter since the connector can be easily described by considering the electrical conditions. This applies to interference immunity as well as interference emission. The coupling inductance is not a measure that applies equally to the entire connector because it can be influenced by the signal assignment on the connector and the connector geometry. Example: As a case-specific example, a maximum coupling inductance of 47 picohenry (pH) was determined for an HDMI signal at a voltage of 4.4 kV. Comparatively, coupling inductance values are between 1 and 4 pH. with the shielded connector.
Of course, data transmission within a PCB system must not be disrupted, falsified, or prevented, which is why protection from electromagnetic interference is a topic of great concern for signal integrity in high-speed systems. Electromagnetic interference can be comparable to crosstalk; the only difference is that the source of interference is not within the individual signal paths in the connector but is produced externally. High-speed data transmissions are particularly susceptible to interference from unwanted electromagnetic effects; even a small impulse can falsify a useful signal and prevent the receiver from clearly interpreting the digital information.
Simulation of an unshielded (above) and a shielded (below) connector. Graphic: ept GmbH.
A shielded connector can offer two positive properties for the user: it is less likely to act as a source of interference while also, due to the presence of shielding, is less likely to be an interference sink for signals. By using shielded connectors, components can be closer to sources
Dependence of the impedance on the rise time. Graphic: ept GmbH.
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