xaccto
Full Member level 5
as the title, I am designing a push-pull DCDC 12V to 400VDC.
Before I start winding the transformer, need to make some decision of how to regulate the 400V.
I can find many example schematics of AC to DC where the DC voltage is lowish using the TL431 and
opto feedback......but not the other way round.
so I thought what if I add another small winding on top of the N3 winding, that being the N5 winding in the diagram. And use
that section to feed the opto feedback circuit.
hmm..I am sure that looks wrong somehow.
at first I thought I might do a direct feedback using a zener diode like I did in this thread https://www.edaboard.com/threads/163362/ that uses a common ground.
But I think an isolated ground might be best, hence looking at the opto f/b design.
The output load on this DCDC will be highly transient, I may even switch off the push pull when the transient events occur, not
sure yet if I have to....
Anyway, looking for any suggestion or comment regarding voltage regulation, Thanks
This is my first dangerous DCDC project :smile:
I have already wound the primary
Does that look ok? i'm using 0.75mm magnet wire there. And you may notice, the 2 windings of the push-pull center tap are wound parallel. 4 strands for each wind.
Additionally you may notice, the wire wound is interleaved, 1 wire of N1, 1 wire of N2 , 1 wire of N1 etc .... is that a good thing or what ? I haven't done that before (did already some low voltage high current DCDC projects)
Before I start winding the transformer, need to make some decision of how to regulate the 400V.
I can find many example schematics of AC to DC where the DC voltage is lowish using the TL431 and
opto feedback......but not the other way round.
so I thought what if I add another small winding on top of the N3 winding, that being the N5 winding in the diagram. And use
that section to feed the opto feedback circuit.
hmm..I am sure that looks wrong somehow.
at first I thought I might do a direct feedback using a zener diode like I did in this thread https://www.edaboard.com/threads/163362/ that uses a common ground.
But I think an isolated ground might be best, hence looking at the opto f/b design.
The output load on this DCDC will be highly transient, I may even switch off the push pull when the transient events occur, not
sure yet if I have to....
Anyway, looking for any suggestion or comment regarding voltage regulation, Thanks
This is my first dangerous DCDC project :smile:
I have already wound the primary
Does that look ok? i'm using 0.75mm magnet wire there. And you may notice, the 2 windings of the push-pull center tap are wound parallel. 4 strands for each wind.
Additionally you may notice, the wire wound is interleaved, 1 wire of N1, 1 wire of N2 , 1 wire of N1 etc .... is that a good thing or what ? I haven't done that before (did already some low voltage high current DCDC projects)
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