PWM Controllers for DC-DC (push-pull) converter

[theoldwizard]

As mentioned before I am a total newbie in this arena, so if this has been discussed please point me in the proper direction.

I am researching building a 500-1000w. Anyone with any familiarity with these devices know that the typical design uses a PWM controller and typically a ferrite core transformer. I was originally thinking about using a TL494 or TL594 but ...

I know you just use it for an example, but just to let you know a TL494 wouldn't be good for a push-pull converter, you'd want a current mode controller for push-pull. TL494 is completely obsolete, ...

Others have told me the exact same thing, specifically about the "current mode control".

My research has led me to the UC2856, permanently now owned/produced by TI. Any other suggestions with justifications ?

I'm certain I am not grasping the fullness of "current mode control" other than there are 2 comparators, one for voltage feedback and one for current feedback. The current feedback comparator has additional circuitry that I do not fully comprehend. Additional insight would be helpful !



Of course along the way I have stumbled across many poor application design, mostly with no feedback !

 

[KX36]

I like the UCC28083 for push pull and full bridge converters. UC2856 looks good too.

Are you sure push-pull is the right topology? Like a single switch forward, it has a relatively high voltage stress on the FETs meaning it's better for lower input voltages. It only really presents a problem for off-line converters in countries that use 220-240V mains though.

If you tell me your input voltage range and output voltage and current I may be able to suggest a topology.

 

[theoldwizard]

Input would be from a 12V lead acid battery, so a range of 10.5-16.0V

Output from this stage would have to be > 190V, even at the low end of the input voltage.