Patent ID: 7292017

Claim:
A capacitor insulating power supply comprising: a first, second and third switching elements connected in series between positive and negative lines carrying DC current supplied through a rectifier circuit from an AC power supply or directly supplied from a DC power source; a switch control circuit for on/off controlling the first, second and third switching elements by a signal of a predetermined frequency; a first capacitor inserted between a load terminal and a connection node of the first switching element and the second switching element, and a second capacitor inserted between a load terminal and a connection node of the second switching element and the third switching element, in which capacity values of the first capacitor and the second capacitor are the same; in the switch control circuit, a phase of on/off of the first and third switching elements are the same; and the phase of on/off of the first and third switching elements is opposite to a phase of on/off of the second switching element.