The circuit was designed with reference to "700-W interleaving transition-mode PFC reference design".
The circuit below is a UCC28064A controller schematic and a PFC main board schematic.
When the load was 0A, the output was confirmed to be 390V.
However, with a load of 0.1A, the output drops to 300V and maintains 300V. The output no longer rises.
The controller does not seem to work.
Please check the circuit diagram.
Thank you.