Common Mode Filters / Chokes CHOKE

hi my name is Alicia slaw from bridge digital and in this short video we're going to talk about common mode chokes operation and why you have got certain amount of differential mode inductance within a common mode choke first let's have a look at the operation of a common mode choke the choke itself looks something like this you can see that you have got two windings so there's one winding that goes on this side and you've got another winding that goes on this side it's effectively a transformer with identical number of windings and the dots being both on the same side so if I draw the two windings on this board I've got one winding on this side and one winding on the other side in practice this would look something like with the dot notation suggesting that the directions are both in one way let's see what happens to common mode currents from what in one of the previous videos we said