| 摘要 |
PURPOSE:To obtain a waveform shaping circuit where the phase of an output signal is not changed even if an input signal level is changed by changing a threshold level in response to the detected output of a peak hold means to an input signal. CONSTITUTION:An operational amplifier 13 converts an input signal into a rectangular wave signal and leads the signal to an output terminal 14 while being operated in the saturated and non-saturated state in response to the level of the input signal applied to its inverting input terminal. An operational amplifier 21 is activated at the active region and amplifiers an input signal V1, the amplified signal is subject to peak detection by the rectifying and smoothind operation of a diode 23 and a capacitor 25 and the detected voltage is held in the capacitor 25. A Schmitt voltage inputted to a non-inverting input terminal of the operational amplifier 13 becomes the sum of the detected voltage and a feedback voltage formed by resistors 17, 18 and since it is changed in repsonse to a peak level of the input signal V1, even if the level of the input signal is changed, a waveform shaping circuit where the phase of output signal is unchanged is realized. |
