Abstract: A resonant converter having a pre-conduction mechanism for realizing a wide output voltage range is provided. The resonant converter includes a first circuit and a second circuit. The first circuit includes a plurality of primary-side switches. The plurality of primary-side switches includes a first high-side switch, a second high-side switch, a first low-side switch and a second low-side switch. The second circuit includes a plurality of secondary-side switches. The plurality of secondary-side switches includes a third high-side switch, a fourth high-side switch, a third low-side switch and a fourth low-side switch. When the second low-side switch and the first low-side switch are turned on and a current time reaches a preset on time, the fourth high-side switch and the third low-side switch are turned on.

Abstract: A resonant converter having a pre-conduction mechanism for realizing a wide output voltage range is provided. The resonant converter includes a first circuit and a second circuit. The first circuit includes a plurality of primary-side switches. The plurality of primary-side switches includes a first high-side switch, a second high-side switch, a first low-side switch and a second low-side switch. The second circuit includes a plurality of secondary-side switches. The plurality of secondary-side switches includes a third high-side switch, a fourth high-side switch, a third low-side switch and a fourth low-side switch. When the second low-side switch and the first low-side switch are turned on and a current time reaches a preset on time, the fourth high-side switch and the third low-side switch are turned on.

Abstract: An LLC resonant converter is provided, which includes an input power source, a full-bridge switch circuit, a resonant circuit, a transformer, a rectifier circuit, a load, and a control circuit. The control circuit includes a load detection circuit and a valley switching circuit. The load detection circuit detects a load state of the load. The valley switching circuit is configured to, in response to the load state being a light load state: correspondingly generate a first difference voltage; calculate a first switch on-time for a first switch and a fourth switch; generate switching signals that control the first switch and the fourth switch to be turned off, and detect voltage valleys of a second switch and a third switch; and generate the switching signals to control the second switch and the third switch to be turned on according to the calculated first switch on-time.

Abstract: An LLC resonant converter is provided, which includes an input power source, a full-bridge switch circuit, a resonant circuit, a transformer, a rectifier circuit, a load, and a control circuit. The control circuit includes a load detection circuit and a valley switching circuit. The load detection circuit detects a load state of the load. The valley switching circuit is configured to, in response to the load state being a light load state: correspondingly generate a first difference voltage; calculate a first switch on-time for a first switch and a fourth switch; generate switching signals that control the first switch and the fourth switch to be turned off, and detect voltage valleys of a second switch and a third switch; and generate the switching signals to control the second switch and the third switch to be turned on according to the calculated first switch on-time.

Abstract: A full bridge converter having a wide output voltage range includes an input power source, a full bridge switching circuit, a transformer, a first rectifying circuit, a second rectifying circuit, a first output circuit, a second output circuit, and a control circuit. The transformer includes a magnetic core, a primary side winding, a first secondary side winding, and a second secondary side winding. The first rectifying circuit includes a first AC switch, a second AC switch and a first freewheeling diode, and the second rectifying circuit includes a third AC switch, a fourth AC switch and a second freewheeling diode. The control circuit, according to a duty cycle, controls the first AC switch and the third AC switch to be turned on during a positive half cycle, and controls the second AC switch and the fourth AC switch to be turned on during a negative half cycle.

Abstract: A full bridge converter having a wide output voltage range includes an input power source, a full bridge switching circuit, a transformer, a first rectifying circuit, a second rectifying circuit, a first output circuit, a second output circuit, and a control circuit. The transformer includes a magnetic core, a primary side winding, a first secondary side winding, and a second secondary side winding. The first rectifying circuit includes a first AC switch, a second AC switch and a first freewheeling diode, and the second rectifying circuit includes a third AC switch, a fourth AC switch and a second freewheeling diode. The control circuit, according to a duty cycle, controls the first AC switch and the third AC switch to be turned on during a positive half cycle, and controls the second AC switch and the fourth AC switch to be turned on during a negative half cycle.