Switching regulator having parallel diode isolated primary windings and plural secondary windings

DETAILED DESCRIPTION The object of the present invention is to provide a switching regulator using one switching control circuit and one switching means and applying chopped voltages to many transformers simultaneously, and generating many mutually insulated DC power sources, which is small in size and has simple printed circuits.
According to the present invention, there is provided a switching regulator comprising: a power supply device; a switching device; a main power transformer, a primary winding of the main power transformer being connected to said power supply device via the switching device; a switching control circuit for detecting a voltage of one secondary winding of the main power transformer and controlling a duty ratio of the switching device; a first diode inserted in series with and in a forward direction to a primary winding of the main power transformer; at least one subsidiary power transformer, a primary winding of the subsidiary power transformer being connected in parallel with the primary winding of the main power transformer; and a second diode inserted in series with and in a forward direction to a primary winding of the at least one subsidiary power transformer.
The switching regulator of the present invention uses one switching control circuit and one switching means and applies chopped voltages to many transformers simultaneously, and generates many mutually insulated DC power sources.
That is, according to the switching regulator of the present invention, the one transformer having many windings is divided into many small transformers, so that the weight on the printed substrate is divided and the space occupied by the printed substrate on which the transformers are mounted, in decreased.
Furthermore, the printed circuits are simplified, the printed substrate is miniaturized, and the packing density of the device is improved.