DC to DC Demystified - Blog 1 - Does it fly back?

RE: DC to DC Demystified - Blog 1 - Does it fly back?

flyingbean — Thu, 11 Jan 2024 19:36:46 GMT

It is very enjoyable to read your blog. Well done!

RE: DC to DC Demystified - Blog 1 - Does it fly back?

scottiebabe — Thu, 11 Jan 2024 17:41:22 GMT

Wiki's definition of flyback:

eliminate flyback, which is the sudden voltage spike seen across an inductive load when its supply current is suddenly reduced or interrupted

en.wikipedia.org/.../Flyback_diode

Great work!

RE: DC to DC Demystified - Blog 1 - Does it fly back?

javagoza — Thu, 11 Jan 2024 09:30:59 GMT

Congratulations [mention:cae42f43dcc24e06afde7807edc3f7b9:e9ed411860ed4f2ba0265705b8793d05] on publishing your first blog! This is a great start and will make it easier for you to continue writing. Setting achievable goals for yourself is important, and you've done just that by planning your next blog. Keep up the good work!

A question: when measuring the leakage inductance I see that you are doing it on the secondary winding and shorting primary and AUX, shouldn't you do it by measuring on the primary and shorting the other two windings?

And if you are not going to use the AUX winding, I think there is no point in short-circuiting it either, that winding would only be affected by the Eddy currents unconnected, no mutual inductance, at least that is what my intuition tells me, I am not an expert in this.

RE: DC to DC Demystified - Blog 1 - Does it fly back?

genebren — Thu, 11 Jan 2024 04:51:52 GMT

Very enjoyable and educational blog. You did a great job on your first attempt. Keep up the good work!

RE: DC to DC Demystified - Blog 1 - Does it fly back?

shabaz — Thu, 11 Jan 2024 01:47:33 GMT

Very well-written blog!

Regarding the comment about what flies back, in the past, it was the electron beam in a CRT (after each rendered raster scan line). I think that has to be the derivation of the term because that was called the flyback period, after each scan line, when the beam had to fly back to the left side rapidly (I think it was the left side!). It just so happens that one could make the transformer do two things at once (with a couple of output windings), i.e., provide the output for the magnetic coil (or electrostatic plate) that would control the beam, plus at the same time generate the high voltage needed to drive the tube in the first place.

Wikipedia is a bit unclear on the topic, but does refer to the TV's CRT horizontal line frequency, which would have been the frequency of operation for the flyback transformer (aka LOPT). Also, flyback is a convenient opposite term to forward, I guess, to distinguish periods of the waveform, for modern times when the original electron beam flyback origin of the term is irrelevant now.

Nice measurement screenshots, is that with an Analog Discovery 3?

RE: DC to DC Demystified - Blog 1 - Does it fly back?

dougw — Wed, 10 Jan 2024 23:19:24 GMT

Great blog. I liked jumping into the example early. You are well on your way to demystifying a complex topic.