| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To miniaturize a switching power supply by reducing the loss of a switching element. <P>SOLUTION: The switching power supply equipped with a conversion circuit for supplying the DC voltage from a DC power supply Vdc1 to the primary winding 3a of a transformer Ta by turning on/off through switches Q1-Q4 and outputting a voltage of positive/negative symmetry from the secondary winding 3b of the transformer Ta comprises a transformer T1 having a primary winding 5 and a secondary winding 5c having one end connected with one end of the secondary winding 3b, a transformer T2 having a primary winding 6 and a secondary winding 6c having one end connected with the other end of the secondary winding 3b, a reactor Lo connected across the series circuit of the secondary winding 5c and the secondary winding 6c, a smoothing capacitor Co having one end connected with the other end of the transformer T1 and the other end of the transformer T2, a diode D4 connected with the joint of the primary winding 5a and the secondary winding 5b of the transformer T1 and the other end of the smoothing capacitor Co, and a diode D3 connected with the joint of the primary winding 6a and the secondary winding 6b of the transformer T2 and the other end of the smoothing capacitor Co. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
