| 摘要 |
PURPOSE:To perform a sinusoidal wave-triangular wave modulation system by controlling a DC voltage in response to the set frequency, counting via a ring counter and employing as a base signal of a transistor a data signal in an ROM. CONSTITUTION:A DC voltage is controlled via controllers 49, 32 peoportionally to a set frequency from a frequency setter 46, an ROM50 which stores a signal obtained via sinusoidal wave-triangular wave modulation and a ring counter 48 which counts in the set frequency are provided. The data signals which are stored in the addresses of the ROM corresponding to the counted values of the counter 48 are applied to the bases of transistors 35-36, 36-39, 37-40. In this manner, the waveform signals corresponding to the angle are stored in the ROM, thereby performing a sinusoidal wave-triangular wave modulation system with a simple circuit. |
