| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switching power supply circuit capable of generating a pulse width modulating signal of which phase is shifted by a half-cycle, using one type of carrier, and preventing a voltage drop and current loss on the output side of a boosting circuit. <P>SOLUTION: A first and a second boosting circuits 6A and 6B are connected in parallel between a DC power supply 2 and a load, and a smoothing capacitor Cout is connected between the output side of the respective boosting circuits 6A, 6B and the load. The first and second boosting circuits 6A, 6B have a boosting coil of which one edge is connected with the DC power supply and in which the DC voltage is applied, the first switching device which grounds or opens the boosting coil and the second switching device which is connected between the other end side of the boosting coil and the smoothing capacitor to be ON/OFF driven. The pulse width modulating signal which is supplied to the switching device of the respective boosting circuits 6A, 6B and of which the phase is shifted by a half cycle is generated by one carrier at a pulse width modulating signal generating unit 7. <P>COPYRIGHT: (C)2007,JPO&INPIT |
