VOLTAGE CONVERSION APPARATUS, CONTROL METHOD, AND POWER SUPPLY DEVICE

This application provides a voltage conversion apparatus, a control method, and a power supply device. The voltage conversion apparatus includes a control circuit. The control circuit is configured to: obtain a first sampling voltage and a second sampling voltage; detect a resonant period based on the second sampling voltage when it is determined, based on the first sampling voltage, that a voltage range of an output voltage of the voltage conversion apparatus changes and a voltage threshold is exceeded; and output a drive signal based on the detected resonant period. The drive signal is used to control turn-on and turn-off of a first switching transistor and a second switching transistor. In this application, a change of a direct current output voltage is monitored, the resonant period of the voltage conversion apparatus is adaptively detected and updated, and then the drive signal is adjusted based on the updated resonant period, so that conversion efficiency of the voltage conversion apparatus is improved under a wide-range output.