The magnetic ring on the VGA cable is also called ferrite bead. Many electronic devices often use this magnetic ring as an anti-interference component. It can be used to weaken high-frequency noise and effectively shield EMI interference. And isolating or filtering out the high-frequency treble pulse interference of the power connection cable into the device circuit; for example, installing the magnetic ring on the cable of the audio and video television can improve the audio and video playback quality.
A good-looking friend will find that there are large or small cylindrical magnetic rings in the cables of the commonly used notebook computers, such as power cables, data cables, display signal cables, etc., according to the needs and actual use. Different, the design size of the ferrite magnetic ring is also different.
What is the VGA cable magnetic ring?
In fact, the VGA cable magnetic ring is closely connected with the power cable, and the entire cylinder together with the cable is a complete cable. Although this cylinder is called a ferrite bead, many netizens prefer to call it a "magnetic ring". The internal structure of this magnetic ring is actually not complicated. It does not need to be energized when it is used. The inside of the magnetic ring is mainly called " Ferrite is made of structural material. Ferrite is a special material, generally made of iron-magnesium alloy or iron-nickel alloy.
What is the use of ferrite filtered high frequency signals?
Ferrites have high electromagnetic resistance characteristics, which can cause great loss to high-frequency signals, but very low signal loss at low frequencies. Simply put, the ferrite in the VGA cable magnetic ring acts to filter high frequency signals, which is equivalent to a high frequency signal filter.
The reason why ferrite filters high-frequency signals is mainly because we have all kinds of signal sources, mobile phone signals, broadcast signals, etc., and current sensing signals, which are all in the category of high-frequency signals. Computer motherboards, CPUs, power supplies, IED data cables, etc. have high operating frequencies, resulting in a large amount of spatial stray electromagnetic interference signals when the computer is running. The intensity of these high-frequency signals is several times that of the computer's external signals.
If the high-frequency signals released by these electronic devices are not filtered, they will affect other signals that are normally transmitted, such as the current noise emitted from the audio equipment, and the TV signal difference, etc., due to interference from surrounding high-frequency signals.
The VGA cable magnetic ring has different impedance at different signal frequencies. When the frequency is low, the impedance is very small. When the surrounding signal frequency increases, the performance of the magnetic ring filter signal will rise sharply, so that the useful signal can pass smoothly. At the same time, it acts to suppress the transmission of high-frequency signals through the cable.
The ferrite in the VGA cable magnetic ring filters the surrounding high-frequency signal, and retains the low-frequency signal transmitted by the cable itself, which can effectively prevent signal interference and has a signal fidelity effect.