Interleaved active PFC: More efficient?

[japlytic]

I happened to stumble across an application for an interleaved active PFC:

https://cdn.badcaps-static.com/pdfs/...65e8167344.pdf
http://www.edn.com/index.asp?layout=...leid=CA6317074

In most cases, the boost inductor PCB area can be reduced by up to 50%, and also allows the use of smaller output capacitors.

I am not 100% sure that an interlaved active PFC is more efficient than an active PFC using a single inductor.

[gonzo0815]

Re: Interleaved active PFC: More efficient?

I think it is not necesarily more efficient than normal A-PFC circuits.
May be, as the ripple is lower and therefore the peak currents are lower too, the loss in the capcitors, wirres or traces and may be in rectifiers ar lower. I think the main benefit is, that lower grade caps can be used. But i haven`t seen this in real wolrd psu`s up to now. I expected the FSP 750w and the Amacrox Free Earth series to be Interleaved active PFC units, but aprrently they are not. From my point of view, and as stated this would be especially for high power units. I think this is, where you would need more than one or two switching transistors anyway, due to the high current. Probably only >600w PSU will come close to this area.