| 摘要 |
PURPOSE:To enable to finely adjust the output voltage of an inverter by providing a pair of memories provided with a counter, applying an adjustable preset value whenever the counted content reaches the prescribed value and controlling ON and OFF the resultant output signal of the both memories. CONSTITUTION:Four transistors U-Y are connected in a bridge to form an inverter, and a DC input voltage E is converted to an AC voltage VL and supplied to a load L. This control is performed through base drive circuits 13, 23 by counting the signal form a clock pulse generator 10 by counters 11, 21, and reading out them from memories 12, 22, in which the prescribed waveform data are written, in response to the counted content. In this case, a voltage control signal VS is converted by a converter 20 into a digital signal, preset by the signal whenever the counted content of the counter 21 reaches the prescribed value, and altering the initial value, thereby finely adjusting the output voltage VL. |
