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RE: Flyback Transformer Boards - Any interest ? ? ? ?



Original poster: "Wall Richard Wayne" <rwall-at-ix-dot-netcom-dot-com> 

Steve,

That's how a flyback is suppose to work.  The shim prevents magnetic
saturation.  It's almost impossible to saturate air.  Think of the air gap
as acting like a huge magnetic "spring" which releases a large amount of
energy rapidly after being compressed.  There is a huge HV peak in the
secondary.  The secondary discharge of a flyback is not a smooth sinusoid
waveform but a sharp spike with a D/C bias.  Flybacks are not just plain
ordinary transformer action.

There is an advantage to push pull flyback mode, but it takes making a
center tapped primary.  Only one side of the primary is active at a time.
Frequency, dwell time and push-pull configuration can be achieved with a
variety of inexpensive PWM driver chips.  BUT, keep the shims intact.

Dan, if you design a dual transistor (push-pull) flyback driver, then those
who want just a single transistor may use just one side.  And, those who
want push-pull can use both sides.


 > Wow, i did not know that!  Even when i roll my own flybacks, i leave the
 > gap spacers in the core.  Hmm, maybe i should test this push-pull setup
 > again and see how it goes with a gapless core.

Good idea.  Let us know how it works.

 >
 > Steve

--- Richard Wayne Wall
--- rwall-at-ix-dot-netcom-dot-com