| 摘要 |
PURPOSE:To generate a DC voltage in response to the periodic variation of an input signal in a 1-period conversion type periodic voltage converting circuit by charging the first capacitor unit it reaches the first predetermined voltage and discharging the capacitor when the second capacitor exceeds the second predetermined voltage. CONSTITUTION:The predetermined voltage 5VD is applied to a capacitor C1 in accordance with the positive phase rectangular signal A of a positive phase and inverted phase generator 2. The output voltage C of the capacitor is compared with the predetermined voltage by the first comparator 7, which produces a charging pulse D to charge the capacitor C2 at the predetermined voltage 7VD. After the time t1/2, the capacitor C2 is discharged at constant current via a constant-current power source IB with the discharge pulse E. Then, the capacitor C1 is discharged with the reverse phase rectangular signal B, the first comparator 7 is stopped. The stored voltage H of the capacitor C3 becomes equal to the stored voltage G of the capacitor C2 with the detected pulse F of the second comparator 10. In this manner, the discharging time t2 of the capacitor C2 corresponds to one period of an input signal and varies in response to the variation in the period of the input signal. |
