| 摘要 |
PURPOSE:To reduce the turning OFF loss of a main transistor by providing an oscillator which outputs a triangular wave signal or a reverse sawtooth wave signal in a pulse width modulator for stabilizing the DC output. CONSTITUTION:A main transistor 4 is driven by a pulse width modulation signal of a comparator 16 to stabilize the DC voltage to be supplied to a load 12. On the other hand, a sub transistor 20 is driven by the pulse width modulation signal of a comparator 26 to stabilize the DC voltage supplied to a load 23. The output signal of an oscillator 27 is a reverse sawtooth wave, and the turning ON periods of the transistors 4, 20 coincide, and the turning OFF time of the transistor 20 is earlier than the turning OFF period of the transistor 4. |
