Resonant power conversion circuit controlled by integral result of feedback signal

A power conversion circuit for converting an input voltage to an output voltage, comprising:

• a transformer, comprising a primary coil and a secondary coil, wherein the primary coil is coupled between a switch node and a resonant node;
• a resonant capacitor, coupled between the resonant node and a ground;
• a high-side transistor, providing the input voltage to the switch node based on a high-side driving signal;
• a low-side transistor, coupling the switch node to the ground based on a low-side driving signal;
• a current detection circuit, detecting a resonant current flowing through the resonant capacitor to generate a current detection signal;
• a feedback circuit, generating a feedback signal based on the output voltage;
• and
• a control circuit, superpositioning the current detection signal to a slope compensation signal to generate a superposition signal and integrating the superposition signal to generate a first integral signal;
• wherein the control circuit further integrates the feedback signal to generate a second integral signal and compares the first integral signal and the second integral signal to generate the high-side driving signal and the low-side driving signal.