OWERTY

[pranav]

...

[Molenaar]

Look up the Mazilli driver, that should do quite well.

[Seekonk]

That transformer will produce DC with its internal diode.

[Zero999]

The simplest way I know of.

http://madlabs.info/flyback.shtml

[james_s]

These are some others, I've built the mk II one and it works nicely.

http://uzzors2k.4hv.org/index.php?page=flybacktransformerdrivers

[pranav]

Thanks. I've made a single transistor driver with 2N3055 but the spikes killed by 2N3055

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[T3sl4co1l]

Thanks. I've made a single transistor driver with 2N3055 but the spikes killed by 2N3055

That's what the circuit is designed to do, by the looks of it.

Tim

[Zero999]

Thanks. I've made a single transistor driver with 2N3055 but the spikes killed by 2N3055

Well the circuit I posted above doesn't use the 2N3055 but the NTE284, which has a much higher voltage rating then the crappy old 2N3055. Failing that, try adding a snubber network.

[T3sl4co1l]

This is a bit more responsible of a design,



And yes, for once I'm claiming a 555 is useful for something.

+V can be whatever.  For instance, you can use about +100V and use the primary winding inside the FBT itself (trace the PCB to find these pins).  For the external winding (usually 3-10 turns), 12-24V will be suitable.

An RCD peak clamp snubber, across the transistor, might also be a good idea, to prevent overvoltage.  The RC damper helps, but doesn't limit the peak very much.

I don't have a complete schematic handy, but you would add a diode, resistor and capacitor, connected to the transistor collector/drain just as Q3, D1, C2, RL are connected here: https://www.seventransistorlabs.com/Images/AltiumDiscreteFlybackSch.png
Typical values would be D1 = UF4007, C2 = 10nF and rated at least 2 x +V, RL = 10k 5W or thereabouts (depending on +V, turns, operating frequency, power level, etc.).  You want RL to be small enough that the clamping voltage (the DC voltage on C2) isn't obscene.

Tim