| 摘要 |
<p>A complex resonance type switching converter comprising a self-excited voltage resonance type converter has a conduction control element (Q2) series-connected to a drive transformer (CDT) wherein a detection winding (NA) and a drive winding (NB) and the control winding (Nc) of a self-oscillated drive circuit are wound around the same core. The current conduction quantity of the conduction control element (Q2) is variably controlled to vary the level of a base current flowing through the base of the switching element (Q1) from the self-oscillated drive circuit, so that the switching frequency is variably controlled. Thus, the conduction angle and the switching frequency of a switching element are varied simultaneously, resulting in the constant voltage control of the secondary side DC output of the converter. Use of this drive transformer (CDT) enables the suppression of a variation in a self-oscillated drive circuit and attains miniaturization.</p> |
