| 摘要 |
PURPOSE:To form the high voltage control circuit of a cathode ray tube which can satisfy the two requests of a power loss and a response characteristic by combining a switching power source with series power source. CONSTITUTION:The frequency of a horizontal synchronizing signal from an input terminal 1 is converted into a voltage in a frequency/voltage converting circuit 2 to obtain the voltage according to the frequency. This voltage is primarily converted in a voltage primary converting circuit 3 so as to preset to the required value of the output voltage of the frequency and the switching power source 4. This converted voltage is inputted to the switching power source 4 and the output voltage is inputted to the series power source 5. The series power source 5 defines a feed back voltage 9 obtained by dividing a high output voltage 7 by a resistance 8 to be a feed back input and the output voltage 10 is controlled so as to constantly maintain this feed back voltage 9. At the time of changing a horizontal deflecting frequency, the output voltage of the converting circuit 2 is received to change the output voltage of the switching power source 4 and control so as to maintain the output voltage 10 of the series power source 5 constantly. |
