摘要 |
A PWM module is provided to output a driving pulse to a switching device in synchronization with a synchronizing pulse having a frequency twice the frequency of the high-frequency current of a primary-side induction line. The PWM module performs output voltage feedback control such that the output voltage of an output capacitor is set at a reference voltage. The module outputs, to the switching device, the driving pulse having a half width of the pulse width of a driving pulse that can be outputted, at the start of power supply to the primary-side induction line. Moreover, the module forcibly performs the output voltage feedback control if an output voltage of the output capacitor does not increase to the reference voltage within a reference time. |