| 摘要 |
PURPOSE:To save man-hours by inserting a lead circuit to a feedback circuit of an operational amplifier to compensate a phase error of the operational amplifier thereby making the calculated value and an actually measured value coincident with each other. CONSTITUTION:An output of the operational amplifier 5 is fed back to the input side via a feedback circuit comprising resistors 7, 9 and a capacitor 8 to compensate the phase characteristic near the cutoff frequency. Thus, the phase characteristic of the operational amplifier 5 near the cutoff frequency is improved and the frequency characteristic of an active filter becomes characteristics nearly coincident with the calculated value. |
