Worth knowing: Inductor Orientation Does Matter! скачать в хорошем качестве

Worth knowing: Inductor Orientation Does Matter!

"The orientation of an inductor doesn't matter." That's just one of many lies professors and teachers tell. It might be true in theory - but in practice, that's not always true. On this PCB, there are two inductors mounted in opposite orientations. Both are connected to the same fast-edge square wave signal, with identical amplitude and frequency. When measuring the electric field strength with an E field probe right next to the inductors, the difference is about 3 dB. Sounds harmless - but that's around 41% more field strength, and twice the radiated power. Inductors don't just emit magnetic fields, they can also become serious sources of electric field noise. Especially when operated at switching nodes with fast voltage transitions. And this is exactly where the internal structure of the inductor, namely the winding direction, makes a huge difference: If the outer end of the winding is connected to the switching node, the full dV/dt appears right at the outermost turns - which are also closest to the surrounding environment. Experienced engineers know: 👉 The start of the winding, usually marked with a dot, should always be connected to the switching node. #electricalengineering #electronics #hamradio #physics