| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a bridgeless boost converter type switching power supply device that easily implements low common mode noise fed back to an input, and a compact and high efficiency design. <P>SOLUTION: First and second boosting inductors 12, 14 have substantially the same inductance, and a smoothing capacitor 16 has a minus terminal connected to a control ground 20. First and second switching elements 22, 26 are turned on/off by a control circuit 30, and rectification elements 24, 28 are turned on/off complementarily thereto. An input line inductor 42 has three windings having the same number of turns, and an output end 48b of the first winding 48 is connected to an input end 12a of the first boosting inductor 12 and an output end 50b of the second winding 50 is connected to an input end 14a of the second boosting inductor 14. An input end 52a of the third winding 52 is connected to the control ground 20, and an output end 52b is connected to the input end 14a of the second boosting inductor 14 via an AC blocking capacitor 44. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
