PFC module using UCC28063A

Vitor goncalves

Other Parts Discussed in Thread: UCC28063A

Hi there,

I'm designing a PFC module using UCC28063A and I'm having a few doubts.

If the output power drawn by the module I'm intending to connect to this PFC output decreases, what happens to the frequency of the UCC28063A? It decreases as well? What's the influence of the frequency clamp on this?

Thanks,

Vitor.

over 9 years ago

0 Vitor goncalves over 9 years ago

Prodigy 100 points

Another thing,

Is there a way to lower the maximum frequency clamp on the UCC28063A?

Thanks,

0 Bing -PSC Lu over 9 years ago in reply to Vitor goncalves

TI__Intellectual 1615 points

When the power decreases, the switching frequency goes up. There is an internal frequency clamping at about 500kHz and you can't adjust it.
However, if you can keep VINAC pin voltage to be a nice rectified sinusoidal wave, the zero crossing compensation can limit the maximum switching frequency that way.

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PFC module using UCC28063A