| 摘要 |
PURPOSE:To reduce the variation in the output power of a chopper with respect to the variation in the output voltage by making gentle the inclination of the output current waveform of the chopper when the output voltage of the chopper is large. CONSTITUTION:A power source has a commercial power source Vs, a rectifier DB, etc., and a chopper has a switching element Q1, a diode, an inductance element L and a capacitor C2, etc. A resistor Rdt detects a current flowing to a load DL which increases when a time is elapsed through a chopper after the element Q1 is turned ON, a comparator CMP compares the detection output with a reference level, and a flip-flop FF turns OFF the element Q1 by the output of the comparator CMP. The reference level applied to the comparator CMP is lowered by the lapse of the time from the time when the element Q1 is turned ON, and synchronized with the period of the element Q1. |
