I just buy them from Coilcraft; their website nags me to order free samples but they gladly sell in single quantities. I usually buy a few other coils at the same time, for future projects.
As far as what voltage a flyback converter produces, I follow these lines of reasoning: - When the primary is energized, it stores energy. Basic 1/2LI^2 . You can use volt-seconds if you wish. - When the primary is de-energized, the inductor will spew all of that stored energy wherever it can. Think of it as a mechanical spring that pops loose. - Your job as the designer is to harvest as much of that energy as possible - The transformer, coupled-inductor, etc will produce any voltage necessary to get rid of it's energy, which includes exceeding the breakdown voltage of the driver transistor. - Make sure all of the energy is removed from the inductor before you energize the primary again. Volts*seconds at the input must equal volts*seconds at the output. - A flyback converter requires a feedback/control mechanism - To reduce the output voltage, you need to reduce the energy-transfer. This can be done by reducing the duty-cycle at the input. - Opposite for increasing the output voltage, but only up to a point. Dont go up to 90% duty-cycle, for example. Instead, increase the input voltage or lower the primary inductance. Beware that current increases. With that in mind, start trolling for research papers on flyback designs; lots of good stuff out there to read and learn from. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/a18fcc79-8320-4e9f-99d7-6359a0faf940%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
