What role does the shielding core winding?

Why do you want to set the anti-jamming core winding? Computer case motherboard, CPU, power supply, and within the IDE cable are working in the high frequency condition, in case there is a lot of space due to stray electromagnetic interference signal, and the intensity of the signal is outside the case several times to dozens times! No circular and USB cable in this space without shielding measures, the USB cable will become very good antenna, receiving clutter in the surrounding environment of high frequency signal, the signal superimposed on the original transmission of signal, even change the original transmission of useful signal, it's easy to have a problem. For higher transmission rate and stability, circular and also in order to reduce the USB line when transmitting data to other devices, such as the interference of sound card, the design and manufacture of magnetic ring, also known as electrostatic shielding layer. The shielding layer is made up of a thin metal foil or more strands of fine woven wire mesh, the application of the surface of the electrostatic field effect, namely the USB data transmission line on the appearance of bread a layer of metal film and the shielding layer and chassis grounding, can well the data line and space interference signal isolation! Still have a kind of absorption core coiling, also called ferrite core winding, when used in the separation of removable magnetic ring, it is commonly used in electronic circuit anti-interference components, have very good inhibitory effect to high frequency noise, the use of ferrite materials (general Mn－Zn） Made of copper under different frequencies have different impedance characteristics, generally in the low frequency impedance is very small, when the signal frequency increases sharply the impedance of the circular and performance. The circular through normal useful signal is very good, and can restrain the high frequency interference signal through very good, and low cost. 1, prevent the plug line current shock produced by interference, prevent instantaneous surge current protection. 2, preventing electromagnetic interference of the space, let the transmission stability. 3, prevent the plug wire when interference current shock, prevent instantaneous surge current protection. 4, to prevent electromagnetic interference of the space, let the transmission stability.