A novel reduction strategy of standby power loss in the multi-oscillated current resonant DC-DC converter considering acoustic noise compatibility

The current resonant type DC-DC converter employs generally the pulse frequency modulation and its magnetizing inductance is set relatively low. For this reason, the magnetizing current through the converter causes a power loss under the light load condition. To solve this problem, a multi-oscillated current resonant type DC-DC converter has been proposed and then the advantage of its control method has been clarified, which can reduce power loss under light load condition and keep low switching noise. This paper deals with a novel reduction strategy of standby power consumption of the converter. As a result, the standby power consumption under no load condition is achieved below 60mW at 100V AC input and 150mW at 240V AC input, respectively. Furthermore, it is clarified that the slope of the resonant current envelope at soft start and end function in the standby mode influence the acoustic noise from the converter.