Hi,
My customer is designed PFC using UCC28070 under the following conditions.
Input : AC85V-265V
Output : DC390V 200W
Efficiency : 90%
Switching frequency : 66kHz
In this case, the following CT requests are required.
Turn Ratio:Nct=Ns/Np=32
Secondary Side Inductance Value : LM=19.3mH
Then, the AL value (19,000nH / turns ^ 2) will be an unrealistic value.
Customer wants to use standard CT that is smaller and cheaper.
Customer is thinking of increasing the switching frequency,
In that case, inductor (skin effect etc.) or MOSFET. He is concerned that the loss will increase.
Could you please advise us to resolve it? Or please let us know your comments.
Also could you please let us know the alternative recommended devices?
The reason to select UCC28070 is as follows:
(1) There is a case of 125V DC input and I think it must be CCM
(2) Since noise standards are strict (low frequency CE101, high frequency CE102, etc.), I think Interleave is good.
(3) We have a track record of development using UCC28070.
Thanks and best regards,
M.HATTORI.
