POWER SOURCE DEVICE

摘要

A power source device comprises an input terminal, a first switching element connected to the input terminal, a second switching element connected to the first switching element, a transformer including a primary coil connected to a connecting node between the first and second switching elements, a low-pass filter of a series circuit of a coil and a capacitor connected to a secondary coil of the transformer, an output terminal connected to a connecting node between the coil and the capacitor in the series circuit, a comparator with a first input terminal connected to the output terminal, an alternating signal generator connected to a second terminal of the comparator, and a temporary-amplitude-generation permissible section via which the output terminal of the comparator is connected to control terminals of the first and second switching elements, respectively.