On 12/22/05, microsoftwarecontrol <microsoftwarecontrol@yahoo.ca> wrote:
> I need to control the output V of flyback/froward
> switch power supply. But it seems very hard, due
> to that isolation transformer, which has fixed tune
> ratio.
>
> I test several switched power supply, after I
> decreased out put V, it shows very low loading
> capability.
>
> Any idea and success about this? Do switched power
> supplies only have fix output V?

 No. Take a look how works the old UC3842-3845 .
The output duty cycle can be modified below 50% or above 50%.
The output loading capability it's a matter of design.

Vasile

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