What is the Cylindrical Plastic at the End of DC Chargers?

Hello buddy, afew days back my brother baught a new laptop, and while it's inspection I found a cylindrical bead at laptop end of it's charger. I think even you might have seen one in cherger of Smartphone (mostly in SONY)  or Laptops. And then very first thing arriving in mind as in mine case is "What is it?". And most of us think it contain some electrical component necessary for charging of device, but what about those devices whose charger don't have this part and why it's always near laptop end? Ever thought of it? I did and this evoked me to gain information about it's constituents, use and importance. With the help of mine school teachers and books, I came to know What actually it's. So to share this information with you people I am here and in this artical I will tell you what that bead contains and what's it's function.

What the cylindrical bead in laptop charger contain and what's it's importance?

Let's first begin with why it's there and to understand it we need to know a few lines about history of DC chargers. So let's start with a bit of boaring history. In the old times, most DC power supplies were of the linear type. That means the box part consisted of a transformer which reduced the voltage and a rectifier circuit which converted the AC to DC. You will remember them to be comparatively heavy. These were really inefficient and wasted more power. But they were electrically silent which means very low electromagnetic noise. In the modern times these got replaced with Switched-mode power supplies which replaces the transformer with a high frequency oscillator. This makes them highly efficient and light weight. The only disadvantage is the extra electromagnetic interference or electrical switching noise getting generated. Now the problem is the switching noise in switched-mode power supplies which can be very strong and sometimes can get into the cable causing interference in the connected device. And to avoid this, Ferrite Bead - a chunk of powdered iron ferrite pressed into a solid ceramic type material is used. It is placed covering the power code very near to the connection point. This ferrite bead acts like an inductor blocking the high frequency (5-100Mhz) noises, so the device using the power supply stays safe. Depending on the design of the power supply, the electrical noise will also vary and hence the different sizes for the ferrite bead is used. So this is how it's important for your device and if you ever try repairing a charger by replacing the connector end, make sure you leave out the ferrite bead while cutting the cable. It is like an extra security for your devices when connected.



I hope it's end of your excitement to know what is in that cylinder. Yeah don't forget to share it with your friends and help them with knowledge.

About Rishabh Ryber

A cyber explorer and enthusiast who is working with computers since he was six. He appears with tricks related to internet, android, Windows, and iOS as well.

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