Purpose Of Bead at the End of Mobile or Laptop Charger

We all have a mobile or laptop charger then,

Ever noticed What is This Bead At the End Of Your Laptop or Mobile Charger?

This is called a ferrite bead or a choke, Basically an electromagnetic wave-bouncer.

What’s Inside Of This Bead

When you open this Ferrite bead, you will not find any complex circuits but only a ferrite cylinder that is magnetic in nature, Which serves the purpose.

Ferrite Bead (source)

What is The Purpose Of it?

when current passes through any cable, it generates electromagnetic interference (EMI). Electronic gadgets generally produce Electromagnetic interference during their operation. 

For example, if you connect an external camera to your monitor, the camera would produce interference and cause your monitor to flicker without the presence of a ferrite bead. if there is not present this bead then Electromagnetic Interference can damage your computer peripherals.

These ferrite chokes ensure that signals are only sent in the intended directions and no Electromagnetic signal is transmitted between the peripherals. The bead minimizes these EMI waves by acting as an EMI blocker. 

Why is This Bead Near To End Of Cables?

This bead’s blocking is most effective when it is near to the source of the Electromagnetic interference, that’s why you will only find these ferrite beads near the end of the cables.