| 摘要 |
PURPOSE:To obtain a sinusoidal wave oscillating circuit with less change in a frequency and an output level due to aging change and with less distortion by inputting an output of a counter to a low-pass filter after processing the output into the stepwise waveform by means of a resistance network. CONSTITUTION:A clock 1 is inputted to a CK terminal of the counter COUNTER. An output of binary 3 digits is obtained at outputs A, B and C, and when the clock is counted from 000 to 111, a signal is inputted to an UP/DOWN terminal to decrease sequentially the value of the counter further, and when the counter value reaches 000, the value is increased again. A stepwise as shown in (3) is obtained for a potential at a terminal X by selecting properly resistors R1-R6. A sinusoidal wave signal is obtained by inputting the waveform to the low-pass filter. |
