| 摘要 |
PURPOSE:To obtain a sinusoidal waveform with required and sufficient accuracy with a simple circuit system entirely by using a method adding a predetermined level so as to obtain a digital data group to obtain a triangle wave, applying digital-analog conversion to the group to obtain the triangle wave and passing the result through a proper filter system. CONSTITUTION:An arithmetic circuit 4 adds a preset prescribed level value as+n.DELTAas to the preceding level value negatively or positively. When the absolute value of the added result exceeds a preset maximum setting value + or -Emax, the level value is added in opposite direction and then the polarity of the addition is made inverse after that point of time. The time series digital data group obtained as the result of operation is converted into an analog quantity by a digital-analog converter 5 in real time, the result passes through a proper filter system 6 such as a band-pass filter to decrease or reject the odd number order harmonics and an object sinusoidal wave is obtained at an output terminal To. |
