| 摘要 |
PROBLEM TO BE SOLVED: To provide a step-down-chopper type power supply unit wherein the density of the mounting spaces of its parts can be increased by a simple means. SOLUTION: On the output side of the switching element of a power supply unit, first and second electrolytic capacitors 3, 4 and a choke coil 5 are so provided that the positive- and negative-electrode terminals of the first electrolytic capacitor 3 are connected respectively with the output side of the switching element and the input side of the choke coil 5, and the output side terminal of the choke coil 5 is connected with the positive electrode terminal of the second electrolytic capacitor 4. Further, the first and second electrolytic capacitors 3, 4 are so mounted on a printed board 6 closely to each other that the lined directions and senses of paired terminals (3a, 3b) and (4a, 4b) of the electrolytic capacitors 3, 4 are made identical with each other, and the choke coil 5 having an electrically insulated encapsulation is mounted on the printed board 6 to be interposed between the first and second electrolytic capacitors 3, 4. Also, on the extension present in the lined directions of the paired terminals of the first and second electrolytic capacitors 3, 4, a metallic plate 7 constituting a case, etc., is existent closely to the capacitors 3, 4.
|
