| 摘要 |
PURPOSE:To obtain a power source device which prevents radiations of high harmonic, etc., by controlling the output voltage while the resonance frequency of the resonance circuit is changed. CONSTITUTION:When a DC output voltage VD becomes higher, the differential voltage in the output of a differential amplifier 42 becomes further positive and the voltage impressed upon the base of a transistor 34 becomes further negative. Therefore, the electric current passing through a controlling winding LC decreases and the inductances of reactor windings LR and L'R increase, because the impedance between the collector and emitter of the transistor 34 increases. Consequently, the resonance frequency of a resonance circuit composed of the reactor windings LR and L'R and a condenser C becomes lower, and both the DC output voltage VD and an AC output voltage VA are reduced. Moreover, by changing the voltage of a reference power source 44, the output voltage can be controlled. |
