| 摘要 |
PURPOSE:To improve the noise resistance by composing a controller of a pulse- width control type switching power source of a C-MOS inverter IC and a capacitor, thereby simplify the construction and reducing the loss of a controller. CONSTITUTION:A DC voltage applied between input terminals 1A and 1B is converted to a high frequency AC by a transformer 3 and a switching element 4, and then again rectified and smoothed by a diode 5 and a capacitor 6. A DC output voltage is detected by resistors 7, 8, and a variation is applied through an amplifier 9 to the input side of a photocoupler 11. A capacitor 16 is charged by the DC output of the photocoupler 11, and when the charged voltage exceeds the prescribed value, an oscillation drive circuit 18 drives the elements 4 to OFF. When the capacitor 16 is discharged, the drive circuit 18 drives to turn ON the element 4 after the prescribed time is elapsed. |
