Hi team,
Could you give me comment on following customer question?
Q1. Does TI have PFC controller IC that has single phase continuous current mode, not current sensing resistor, but current sensing by CT? The customer considers similar to UCC28070 configuration and interleaved CCM.
Best regards,
Takeshi Sasaki
Hello Sasaki-san
The short answer is no. The single channel, CCM PFC controllers in our portfolio all use Average Current Mode control. The average input current is not zero of course so it's not possible to use a current transformer to do this so a current sensing resistor in the input path is needed. Here's a typical application sketch with the current sense resistor circled in red.
However, I think the customer should consider using a current sensing resistor - for example the UCC28180 PFC controller https://www.ti.com/product/UCC28180 device uses an especially low value of current sensing resistor (18mOhm) to minimise power dissipation and the 900W reference design TIDA-00443 achieves 98% efficiency https://www.ti.com/tool/TIDA-00443
It uses leading edge modulation to avoid the need for a high voltage resistor chain for input voltage sensing - this saves space by eliminating the resistors themselves and their associated creepage and clearance areas on the PCB.
I'd recommend the customer look at the UCC28180 or the UCC28019A devices.
Please feel free to ask any further questions on this topic and I'd be delighted to answer them.
Regards
Colin
