Using EG1654 as the PFC controller and EG6599S as the LLC controller. After full-bridge rectification of the input voltage, it is boosted to 390V by EG1654, and then converted into a 36V DC output voltage through a half-bridge LLC topology. Under full-load conditions, the overall system efficiency is 93% with 220V AC input and 90% with 110V AC input. In addition, this design also includes multiple built-in protection functions, including output overcurrent and short-circuit protection.

Based on the EG1654A chip's continuous mode APFC solution, with an input voltage of AC 85V - 265V, achieves stable voltage output of DC 380V and rated power of 600W through dual closed-loop control, featuring low THD, high PF (up to 0.998), and high efficiency (minimum 91.5%). It provides detailed explanations of the main component parameter selection and calculation methods, as well as typical waveforms, PCB design, and component lists.

Compared to the passive power factor correction circuit composed of bulky inductors and capacitor filters, this solution adopts an active power factor correction circuit with better power factor correction performance and higher power density, which has been widely applied. The active power factor correction circuit incorporates a DCDC switch-mode converter between the rectifier and the load, using control techniques to automatically track the input current waveform with the AC input sine voltage waveform, thereby reducing THD and improving power factor.