| 摘要 |
PURPOSE:To generate a digital waveform data of a low distortion rate extending over the whole range by using an ROM which stores the digital waveform data with necessary accuracy. CONSTITUTION:One period of an analog signal is sampled by (frequency of a sampling pulse/frequency of a time base minimum resolution), and its sampled value is stored as a digital waveform data in an ROM10. Also, a set value of a frequency setting device 11 is supplied to an adder 12, and an output of the adder 12 is supplied as an address signal to the ROM10, and also supplied to a latching circuit 13 to which a sampling pulse is supplied. Subsequently, an output of the latching circuit 13 is provided to the adder 12 and added to an output of the setting device 11. On the other hand, a digital waveform data outputted from the ROM10 is multiplied by an output of a level setting device 15 by a multiplier 14. In this way, the digital waveform data of a low distortion rate is generated extending over the whole range. |
