| 摘要 |
PROBLEM TO BE SOLVED: To provide a switching power supply device capable of performing an interleave operation even when its output voltage differs from an output voltage of the other party, and a power supply system having excellent noise resistance configured using the same.SOLUTION: A switching power supply device comprises: an output voltage detection circuit 26 which outputs an output voltage signal Vo1; an auxiliary control circuit 30 which outputs a switching signal Vsw; and a main control circuit 28 which generates a driving pulse V22 of a main switching element 22 on the basis of Vsw. The auxiliary control circuit comprises clock generating means 32, processing means 34, and frequency dividing means 36. The processing means operates upon receiving a clock signal Vck. A fundamental frequency division number A, a prescribed first reference time ta, and a prescribed second reference time tb are set in the processing means. Operating mode is set to short-width pulse output mode or short-width pulse detection mode by an operating mode setting signal Vmo. The processing means determines a timing of inversion of the switching signal Vsw, issues a command to the frequency dividing means tailored to frequency division number specification, and outputs a short-width pulse Vsy. |
