Experimenting with Magnetic Components - Make your own Inductor

RE: Experimenting with Magnetic Components - Make your own Inductor

robogary — Tue, 26 Oct 2021 19:02:22 GMT

very neat idea on mag field reduction with twisted windings

RE: Experimenting with Magnetic Components - Make your own Inductor

Jan Cumps — Tue, 26 Oct 2021 18:30:08 GMT

A magnetics topic that's not that much talked about here, is planar PCB transformers.

Planar transformer surrounded by a ferrite core

(two half cores that connect trough rectangular openings in the PCB)

10 layer board with 5 primary windings and 1 secondary winding

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Layers 1,4,5,7,10 dedicated to the secondary side (each one turn in parallel) and the other to the primary side (one turn each in series).

The stacking goes S PP SS P S PP S (S=secondary P= primary).

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These are inductors worked into a PCB. I've reviewed a 5:1 10-layer one here: https://www.element14.com/community/groups/power-management/blog/2017/02/10/gan-point-of-load-converter-48v-to-1v-50a-pa… .

RE: Experimenting with Magnetic Components - Make your own Inductor

Jan Cumps — Mon, 25 Oct 2021 15:00:47 GMT

I'm running into my lab's limits when trying to measure the differential noise.

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I'm using a known noisy supply as input (noisy in the RF range), and try to show how how the common noise part is rejected.

It looks impressive on the oscilloscope, but it's deceiving. I get the same image when I unplug the supply.

There are times when you have to admit that you're not equipped for a particular test.

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