| 摘要 |
PURPOSE:To reduce loss and to improve high-speed follow-up feature, by controlling the output pulse width with the detection signal of voltage obtained at the output electrode of the first switching element, and by controlling the second switching element with the output pulse. CONSTITUTION:A diode 3 for damper and a capacitor 4 for resonance are connected in parallel to a transistor 1, to which a series circuit is connected in parallel which is made up of a capacitor 5, a choke coil 6 and a diode 7. Furthermore, a power source 9 is connected through the primary coil 8a of a flyback transformer 8. A transistor 13 is switched ON through a PWM circuit 12 at the secondary side output of the transformer 8. At this moment, by exchanging the position of the coil 6 for the capacitor 5, the series system of a diode 15 and a resistance 16 is connected between their contact d and an earth. Thus, the ringing voltage set up when the diode is OFF appears at the contact d of the coil 6 and capacitor 5, so that the current can flow to the diode 15 and the resistance 16. |
