| 摘要 |
PURPOSE:To perform the boost up operation and to extend the control range of voltage variation with low loss, by controlling the conduction period of the switching element in one horizontal synchronizing period. CONSTITUTION:The coil 16 is connected between the positive polarity of the boost up capacitor 11 and the one end 13 of the flyback transformer winding 7c for boost up, the flywheeling diode 17 is connected between the one end 13 and the junction of the coil 16 and ground, and the switching element 13 is placed between the input terminal 9 of power supply and another end 12 of the winding 7c, and the element 15 is controlled for conduction within one horiaontal period with the control circuit 14, which determines the conduction period of the element 15 relating to the terminal voltage of the capacitor 11. |
