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.
结果表明，低通滤波器的截止频率、阶数和类型对检测电路的动态响应过程、检测精度都有很大影响。
2
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。
3
Removing high frequency noise pulses by a low-pass filter and Schmitt-trigger.