Patent ID: 9564818
Date: 2017-02-07
CPC Classifications: H02M,Y02B

Claim:
1. A DC/DC converter comprising: a transformer interposed between an input and an output of the DC/DC converter; a main MOS transistor connected in series between a primary side inductance of the transformer and a ground potential; a synchronous rectification MOS transistor connected in series between a secondary side inductance of the transformer and the ground potential; a refluxing MOS transistor connected between a secondary side output of the transformer and the ground potential and capable of refluxing an output current of the DC/DC converter; and a controller connected to the main MOS transistor, the synchronous rectification MOS transistor and the refluxing MOS transistor, and configured to control input currents and output currents thereof, wherein, when an operation of the DC/DC converter is stopped at a predetermined time, the controller stops a driving pulse of the main MOS transistor, controls duty cycles of pulse width of a driving pulse of the synchronous rectification MOS transistor and a pulse width of a driving pulse of the refluxing MOS transistor for a predetermined period of time from the stop of the driving pulse of the main MOS transistor in a pulse width modulation scheme by a soft stop operation, and, after a lapse of the predetermined period of time, stops the driving pulse of the synchronous rectification MOS transistor and the driving pulse of the refluxing MOS transistor.