| 摘要 |
<p>Provided is a power supply circuit including a synchronous rectification circuit, which is prevented from being wrongly activated. A power supply circuit (1) comprises a first output system (4) including a first transformer (7) for transforming alternating-current voltage and a secondary side rectification circuit (8) for generating voltage of a direct current including a pulsating current from the alternating current of the first transformer (7), and a second output system (5) including a second transformer (10) for transforming alternating-current voltage, MOSFETs (39, 40), and a synchronous rectification circuit (11) for generating direct-current voltage from the alternating-current voltage of the second transformer (10) by the control of the MOSFETs (39, 40). The power supply circuit (1) further comprises a synchronous rectification control circuit (15) for generating a voltage waveform for controlling switching between opening and closing of the MOSFETs (39, 40) from the direct-current voltage of the first output system (4).</p> |
