| 摘要 |
PURPOSE:To easily obtain a damped waveform by accumulating the charge corresponding to a potential difference between an input and an output of an inversion amplifying circuit in an accumulation capacitor, shifting this charge stepwise to a charge/discharge capacitor and decreasing gradually the accumulated charge of the accumulation capacitor, and decreasing the voltage difference between the input and the output of the inversion amplifying circuit by following it up. CONSTITUTION:In an initializing period, among each switch SW1 - SW5, the SW1, the SW2 and the SW5 are closed, and the SW3 and the SW4 remain opened. An input and an output of an inversion amplifying circuit 1A are short-circuited since they are closed by the SW2, input and output voltages of the circuit 1A become equal, and when a power supply voltage is denoted as VDD, an inter-terminal voltage of an accumulation capacitor STC becomes 1/2 VDD, and the charge is charged through the SW1. In a waveform generating period, the SW1 and 2 are closed and as for the SW4 and 5, the opened and closed states are inverted alternately, therefore, at the charge time when the SW4 is closed and the switch 5 is opened, a part of the charge accumulated in the capacitor STC is charged to a charge/discharge capacitor CDC, and the potential difference between the input and the output of the circuit 1A decreases by a portion moved to the CDC. |
