Boost converter with high power factor

A boost converter with high power factor, comprising:

• a bridge rectifier, generating a rectified voltage according to a first input voltage and a second input voltage;
• a divider and filter circuit, generating a divided voltage according to the rectified voltage;
• a capacitive adjustment circuit;
• an induction circuit, coupled through the capacitive adjustment circuit to the bridge rectifier;
• a power switch element, selectively coupling the induction circuit to a ground voltage according to a PWM (Pulse Width Modulation) voltage;
• a PWM IC (Integrated Circuit), generating the PWM voltage;
• an output stage circuit, coupled to the induction circuit, and generating an output voltage;
• a feedback circuit, generating a feedback voltage according to the output voltage, wherein the feedback circuit comprises a linear optical coupler;
• and
• a multiplier, generating a product voltage difference according to the divided voltage and the feedback voltage;
• wherein the capacitive adjustment circuit is selectively enabled or disabled according to the feedback voltage;
• wherein the induction circuit selectively provides a compensation current according to the product voltage difference.