Why do you want to set the anti-jamming core winding?

Along with the expansion of digital equipment, USB cable into a small equipment essential to the user, of course, take the initiative to buy USB cable less friend, under normal circumstances are attached with cable, buy an MP3 player, mobile hard disk, digital cameras or mobile phones, will take the corresponding data line, but even go to the market to buy, the price of this core coiling cable is cheap, average price is around 5 yuan, even two or three dollars cheaper. Common USB line is divided into two major categories on the market, one kind is a USB extension lines, another kind is mini USB cable, the latter shall, in accordance with the specifications in large, medium can be divided into three kinds, and medium size of mini USB cable in the picture below is for common, at present most of the MP3, part of the mobile phone, digital camera, mobile hard disk are used this specification look from the exterior, two USB line, from both ends of the work of the interface and there was no significant difference between both, the only difference is one of them with a cylindrical. 1, the core against plug wire winding when interference current shock; 2, preventing electromagnetic interference of the space, let the transmission stability. 3, prevent the plug wire when interference current shock; 4, to prevent electromagnetic interference of the space, let the transmission stability. EMI absorption magnetic ring/magnetic beads from used to inhibit signal lines, peak power line noise and interference, it have ability to absorb electrostatic pulse at the same time, using electronic equipment electromagnetic compatibility ( EMI / EMC) And the corresponding international standard of electrostatic discharge. EMI absorption circular/magnetic beads absorption interference ability is characterized by the impedance characteristics, present low sensibility in low frequency impedance value, does not affect the useful signal transmission on the data line or telecom, at high frequencies, about 10 MHZ, impedance increases, the inductance component remains small, resistive quantity increases rapidly, the high frequency EMI interference energy in the form of heat absorption dissipation, circular and usually use two key points of frequency 25 MHZ and 100 MHZ calibration EMI resistance to absorb magnetic ring/absorption properties of magnetic beads.