A resonant converter includes: a rectifier bridge; a first capacitor coupled across output terminals of the rectifier bridge; a diode with its anode coupled to a first terminal of the first capacitor; a second capacitor with a first terminal coupled to the cathode of the diode, and a second terminal coupled to a second terminal of the first capacitor; a first transistor having a first terminal coupled to the first terminal of the second capacitor; a second transistor having a first terminal coupled to a second terminal of the first transistor, and a second terminal coupled to the second terminal of the first capacitor; a resonant tank having a first input terminal coupled to the first terminal of the first capacitor, and a second input terminal coupled to the second terminal of the first transistor and the first terminal of the second transistor; and a rectifying and filtering circuit coupled across output terminals of the resonant tank, and configured to provide an output signal to a load.