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Please if anyone know something about DC DC Converter for Citroen Saxo or Cangoo, Please help-me

[werty]

High voltage ,"off line" is 110 or 220 vac input and
some lower DC ...

We use a single NPN transistor
and it is made to oscillate continously .
To regulate , you simply pull down on
the base ( ground it) to shut it off .
You still need an OPTO ( $0.20 ) to feed
back the error signal . I have some the OPTO
actually pulls the base to ground , by itself !

110/220 is rectified to about 160 or 310 DC .
then simply applied to the primary .
Only one transistor is hooked to this primary and
as i said , it oscillates continously , from a 3rd winding
on the core , so you must turn it off prematurely to
regulate the output VDC .

Secondary winding needs only one diode to rectify the secondary
DC voltage . At this high freq , very small coils
will work fine , but caps must be 105 C for the freq
is much higher ( 50khz to 120 khz ) .

There are no limits to this circuit . It can step down , up , or ..
It is very efficient , above 80% .
The automotive inverter uses 2 transistors in push pull , BUT
could easily use the 2 transistor in 2 separate circuits
to do the same high eff' output ! And eliminate
the regulator I.C. that phases the 2 ! Just slave one
to the other with a cap .
Engineers are afraid of the oscillation , they want an IC
to do the timing . But they are wrong in doing so !

1) No dead band to control !
2) no complicated DC drive circuits , its a low cost
additional winding on the core !
3) every ferrite core today has square enuf curve to
not create heat in this self osc' mode .
4) It does NOT spend time in the off mode to
create high ripple !
5) you can't burn up the transistor from
saturation of core , cause the core IS in saturation
mode to turn off the transistor !
It is fault tolerant , like no other !

Any companies in MX want to give me a letter to
obtain my FM3 "Business" ?