Hi All,
I would like to find a symbol for a flyback transfomer. I would need something like this:
I have had a look in snap EDA and I can’t find anything. It would be very helpful, thanks
Kinda hard to tell from that but is the bottom winding actually a secondary that is placed in a more convenient spot for the schematic?
Ha!
Pretty much impossible without knowledge of the rest of the circuit. 
MUCH LATER EDIT: Double Ha!!! It is a feedback winding because if says so (Nfb).
It seems, amongst all the other ailments, I’m going blind. 
@Winsu
Making symbols or footprints is not difficult. Once the learning curve has been mastered (maybe an hour) it is usually quicker to make or modify a symbol than try to find one.
Here and the FAQ are good places to start.
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I agree heartily and stomachily. FWIW I have attached my own custom magnetics library. I do not remember what is in there but you are welcome to use whatever you want that is there.
Bobs_Custom_Magnetics.kicad_sym (14.9 KB)
But my question is what are you going to do if you need a mosquitofront transformer? 
OK after posting I decided to launch KiCad and have a look. There are only a couple of symbols which represent transformers which I hand wound on PQ20/20 cores and bobbins. I guess it is unlikely that you can use exactly those, but they are examples and may provide some starting material. I think I copied the basic looping transformer shape from something in the standard KiCad symbol library. I also have at least one PQ20/20 footprint which I can post if you need it.
I’m assuming you have a personal symbol library.
To modify the Tx Herman selected so it suits your requirements:
Find that transformer in the Device library, highlight (double left click) it, right click it then “save as” from the list.
Give the tx. a new name then scroll to your personal library, highlight your personal library then save.
Staying in the symbol manager, leave the device library, go to your personal library, double click the saved transformer.
Now start to modify.
The symbol editor works much the same way as the schematic editor, with the same keys and functions.
Make sure your Grid is set to 50mil.
Block the whole symbol then press x… symbol will rotate around Y axis.
Double click each pin, in turn, altering the length, number and orientation as required (I altered all the lengths to 100, changed 4 numbers and 1 orientation - pin 6).
Block the 3 windings in turn and move to approximately the required position.
Make some arcs (in green box) using the arc tool (red arrow) and move them to the required places, or make them in place.
Move the pins to the places you wish.
Add some short lines using line tool (red arrow) to join arcs to pins.
Change grid to 1mil. and zoom in to tx lines ( this is required because the lines are off the 50mil grid).
Select each line in turn and extend with the D key.
Double click LH line and increase width… I made it 15.
Use “Add a circle” to create turns dot then select “fill with body outline colour” (to make the small dot a small grid is required, if a 50mil grid is used here the dot will be too large).
Change Grid back to 50mil
Change your origin point to something suitable (blue arrows). I chose pin 1.
Use the “T” to add text if required.
Save… all done.
This took ten times longer to write-up an explanation than it took to do.
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Indeed, that is what I need that the auxiliary winding is placed next to the primary
Thanks, I am going to do an AC/DC converter to then out to USB ports (5V and 1A).
Thanks for the explanation. I don’t actually need to modify the symbol I just had to rotate and re-assignate the pin numbers. I will make good use of your explanation as it will be useful to make more customized symbol. This is the result:
Thanks. Do you have experience in designing AC/DC converters?
SERIOUSLY:
I am a power supply design engineer, and I do not recommend this unless you know how to do a safe design. These days, there is no way to build your own as cheaply as you can buy one (or use a leftover from some retired appliance). I have a bunch of power adapters from laptops and other devices. I would start with that SELV and convert that voltage to what I need. Do you know what is SELV without looking it up? (If you do not, that is a big warning…)
No worries, the transformer will be done in way that it will be completely isolated. Triple wire insulated or 3 layers or insulated tape. No current path to ground from the secondary…
You have not given me the “warm fuzzy feeling” that I seek…
Lots of things now come with an external converter now.
I am familiar with SELV, I work designing LED lamps so power electronics as well…
Bob has a valid point, you will not be able to make this as cheaply or as small as a COTS module.
Not to say you shouldn’t do it in Kicad as they are nice miniprojects to get use to the full flow of Kicad.
Still its valid to raise concerns since we do not know peoples background here and it’s one thing to build some RPi replacement, it’s a totally different ball game to mess with the mains directly. Even though I design 1MW converters, it still scares me, especially when producing something that would appear at face value falls under the LV directive “oh its a USB debug interface, it must be safe” … maybe, hopefully … even with 2 independent levels of signal isolation and 2 independent levels of power isolation to the 3l inverter… “joe average” is not someone with specific electrical knowledge
No COTS fits in the housing…
I once gave advice to someone that got it screwed up pretty bad. Even if I HAD told him to short out the light bulb, the maintenance manager of a complex of several lake side, high rise apartment buildings should have known not to do that. That was a valuable lesson to me on giving advice.
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