我正在使用UCC28056设计Boost PFC电路，但是不理解图中箭头所指的二极管D1的作用是什么
The parallel diode is used for inrush current to charge the output capacitor during startup. Once the output capacitor is fully charged, the converter will start switching and the diode will not be used.
Thank you so much for the helpful answer! I really appreciate it.
