| 摘要 |
PURPOSE:To reduce low-order harmonic components by using the calculated result from the remainder produced by subtracting a pulse time width from a carrier period as a pulse shifting time, and bringing the center of the period into coincidence with the center of the pulse. CONSTITUTION:A signal is fed from an oscillator 21 to a carrier period counter 22, a pulse shift counter 23 and a pulse width output counter 24. The time width P of a pulse formed by switching the carrier and a signal wave and a carrier period C at this time are calculated by a data calculator 25 to obtain a pulse shifting time S. The calculator 25 repeats the calculation at every period of the carrier. Thus, the counter 22 sequentially outputs signals at every period of the carrier according to the data set to the counters to trigger the counter 23, thereby outputting a signal of the time width S, thereby triggering the counter 24. Thus, the counter 24 outputs a pulse of the time width P, thereby bringing the centers of the pulses in coincidence. |
