The active filter acts as an infinite impedance to the external for the fundamental frequency and as a low resistor for harmonic frequencies.
对外电路而言，在基波频率下有源滤波器被控制为无限大阻抗，在谐波频率下被控制为小电阻。
2
Removing high frequency noise pulses by a low-pass filter and Schmitt-trigger.
用一低通滤波器和施密特触发器排除高频噪声脉冲。
3
The simulation result shows that the dynamic response and the detection precision in detection circuit can be greatly influenced by the cut-off frequency, order and type of low pass filter.