| 摘要 |
PROBLEM TO BE SOLVED: To provide a small-sized switching power-supply device that achieves a configuration in which thermal problems due to flowing of a large current hardly occur and has high efficiency and excellent assemblability, in a printed circuit board on which a switching element for secondary-side synchronous rectification of an insulating DC/DC converter circuit is mounted.SOLUTION: Secondary-side coil conductors 122 and 123 of a transformer 120 are disposed so as to be overlapped with a primary-side coil conductor 121 interposed therebetween. End portions 122a, 122b, 123a, and 123b of the secondary-side coil conductors 122 and 123 are electrically connected to drain terminals D of secondary-side switching elements 131 to 134 via connecting wiring patterns 421 to 424 on a printed circuit board 410. |
