| 摘要 |
PROBLEM TO BE SOLVED: To obtain a forward type switching power supply in which an input higher-harmonic current and an inrush current are reduced. SOLUTION: The switching power supply has a rectifying means 2, an input- voltage detecting means 9, an output error voltage detecting means 12, a multiplier 17 outputting the product of the input-voltage detecting means and the output error voltage detecting means, a switching element 5, a switching-element current detecting means 18 detecting the current of the switching element 5, a comparator 19 comparing an output from the multiplier 17 and an output from the switching-element current detecting means 18 and sending an output when the output from the switching-element current detecting means 18 is made larger than the output from the multiplier 17, and an oscillation means 35. The switching element 5 is turned on by an output from the oscillation means, and turned off by the output from the comparator 19. |
