Need for Shielding
Sometimes there is a need to transmit power, low speed control and high speed data signals all in the same harness. While the micro-coaxial cables provide shielding to electromagnetic field and keep it inside the cable these full 360 degrees EMI shielding metallic cover over the mated signal contacts, called ZenShield® prevents the high speed signals to interfere with antennas and other surface mounted components in close proximity. ZenShield is included on the plugs for flexible printed circuits (FPC), micro-coaxial, and Twinaxial cables in CABLINE® series products to cover both the signal contacts and soldered tails of mated connector. ZenShield® is offered in CABLINE®-VS II, CABLINE®-VS IIF, CABLINE®-CA II, CABLINE®-CA II PLUS, CABLINE®-CA IIP PLUS, CABLINE®-CA IIF, CABLINE®-CX II and CABLINE®-UM series products.
As electronic devices are evolving to be more high-performance, power-saving, and compact, the high speed signal requirement in these devices increases, the number of electronic components operating at lower voltage increases and the density of mounted electronic components becomes higher. If electromagnetic noise is added from the outside, unnecessary current may be induced to the circuits in the devices causing a malfunction or damage to high-performance electronic components which may also lead to electronic device breakdown. Also, in electronic devices with wireless communication functions (for example, notebook PCs, tablets and mobile phones) electromagnetic waves generated within the devices can add to the wireless communication circuit noise which can affect antenna reception performance.
In such cases, in general, the measures against electromagnetic noise inside the device are implemented by incorporating electromagnetic noise filter components into the circuit and/or physically blocking the electromagnetic noise by adding a metal shield that covers the components.
With the introduction of smaller devices and high density of mounted components, and the high speed signal communication within these devices, it is imperative to take measures against electromagnetic noise at the jumper connections in devices. I-PEX has developed a high-performance EMC connector series (ZenShield®) that solves electromagnetic noise in the connector by using an appropriate grounding structure and cover which includes the mounting position of the signal contact tails with metal shields. This solution is widely adopted by many customers to prevent electromagnetic interference, especially in high-performance devices equipped with wireless communication functions such as Wi-Fi, GPS, and LTE.
Both shielded FPC and High performance micro-coaxial cables can be used to minimize the RF emissions, leakage and contain the high speed data signals with in the cables. Shielded structure of Micro-coaxial cables also allows to supply DC power signals by using inner center conductor for DC voltage and outer shield for return current. Use of Micro-coaxial cables for power transmission is specially helpful to ensure clean supply voltages in noisy power switching mode applications like servo motor control circuits in Robotics etc.
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NO Signal 1. Antenna |
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No electrical noise from connector to the outside Electromagnetic Interference (EMI)
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Protect the transmission signal from outside electrical noise Electromagnetic Susceptibility (EMS)
In a high definition Display System, exposed tails of graphics connectors typically radiate EMI noise at Nyquest frequencies which interferes with many wireless carrier frequency bands. This high frequency EMI noise also affects the quality of Graphics on the display. For this reason, a shielded Graphics Display connector with integrated solder tail shielding feature must be used for high frequency signal transmission as shown in the figure below. More details about EMI shielded connectors can be found at WEBINAR: EMC Shielding Connectors
