Apparatus for supplying high and medium output voltages with a single transformer, having switchably variable feedback means for controlling the input current to the transformer

Abstract

Abstract A high-voltage power supply apparatus comprises a transformer, and an input winding is turned on and off repeatedly by a switching element, and thereby an alternating current (AC) is generated in the input winding. By varying a turned-on state or a turned-off state of the switching element, a voltage outputted from an output winding of the transformer is regulated. An output voltage of a dividing circuit which is constituted with two series resistors and divides an output voltage is compared with a reference voltage by a comparator, and a control signal in accordance with an output of the comparator is given to the switching element. A switching circuit is connected to one of the resistors of the voltage dividing circuit in parallel. When a switching circuit is turned on, the output voltage of the voltage dividing circuit becomes relatively small and a voltage of the AC generated in the input winding becomes high, and therefore a voltage of a magnitude required for both the high voltage circuit and the medium voltage circuit is obtained from the output winding. When the switching circuit is turned off, the voltage of the AC becomes low, and therefore a voltage required only for the medium voltage circuit is obtained from the output winding.

Inventors

• 👤 Yukio Maeba
• 👤 Kiyoteru Igashira

Bibliographic Details