OUTPUT-NOISE REDUCTION DEVICE

摘要

The purpose of the present invention is to provide an output-noise reduction device that can prevent noise from an electronic apparatus that is housed in a metal casing from being transmitted by electromagnetic coupling. A conductive bar (11) has one end part that acts as a connection terminal that is connected to an output end of a switching power source (5), has another end part that acts as an output terminal (VO), and draws to the outside an output voltage that is outputted from the switching power source (5). The conductive bar (11) passes through a through hole of a magnetic core (13). Chip capacitors (37) are mounted to a mounting substrate (17), and the output terminal (VO) and a ground (GND) are connected by means of the chip capacitors (37). Electromagnetic coupling from an electronic apparatus is isolated from an area that is from the output terminal (VO) to at least a portion of the chip capacitors (37) that are mounted to the mounting substrate (17). Electromagnetic coupling from the switching power source (5) is suppressed. As a result, electromagnetic coupling between the switching power source (5) and an output-terminal-(VO)-side portion of a capacitor (C1) is suppressed, and transmission of noise to the output terminal (VO) is suppressed.