Have you ever noticed the small cylindrical module near the end of your charger? If you haven’t noticed yet, now just take a look at the end of your charger or device plug, it must have some sort of plastic cylinder near to the end of the cable, right?
What Is That Little Cylinder on the Cable of Your Charger?
Well, it might look like a useless addition, but without this little thing, your lappy wouldn’t be able to function properly. Here’s why.
That little cylinder is called a Ferrite Bead.
The cylindrical device is known as a ferrite bead, which is nothing but an inductor (passive electric component) that suppresses high-frequency noise in electronic circuits.
The ferrite bead isolates your laptop from electromagnetic noise, either from the waves that are picked up by the wire or from the existing noise in the AC-DC converter or the AC line.
While you find this cylindrical module common for laptop cords or other electronic devices such as printers, you won’t find this extra piece on other chargers like that of a cell phone. This is because unlike cell phones or other devices that need to be charged (i.e., your iPad or tablet), laptops tend to have many moving parts working at once. This can create a lot of chaos and disorder if the parts aren’t working together, even capable of producing radio frequencies. The case around the laptop charger dulls those vibrations and stops them from causing any interference.
Ferrite beads are made of a hollow disc, an iron oxide material with magnetic properties. It helps to prevent the wire behave on over floating current like aerials. As a result, all this metal wire can potentially serve as an antenna by absorbing or emitting any radiation while passing current around it. Without this ferrite bead, the radiation emitted by the wires could cause interference with other electronic objects around them which act as receptors of this radiation, causing, for example, noise in speakers.
This is why you find those small cylindrical modules at the end of the cables.