| 摘要 |
PURPOSE:To obtain a stable output even with reference to a DC power supply wherein a power-supply voltage fluctuates comparatively largely and an output voltage is low. CONSTITUTION:The positive side of a DC power supply 11 is connected to the middle point of a primary winding 14 for a transformer 13, the negative side is connected to both ends of the primary winding 14, a capacitor 20 is connected across both ends of the primary winding 14, and both ends of a winding 17 for feedback use are connected respectively to gates tor FETs 15, 16. The connecting point of a choke coil 12 to the primary winding 14 is connected to the negative side of the power supply 11, a constant-voltage circuit 26 is connected to both ends of a capacitor 29, and a bias voltage with reference to the gates for the FETs 15, 16 are formed by its constant-voltage output. The FETs 15, 16 are turned on and off alternately and oscillated, their oscillation voltage is obtained from the middle point of the primary winding 14, the peak value of the voltage is about sq. rt. 2 times the voltage of the power supply 11, and the capacitor 29 is charged by its peak voltage. |
