Low pass filter

SECOND ORDER LPF Second-Order Filters are also attributed to as VCVS filters since Op-Amp used here is Voltage Controlled Voltage Source Amplifier. This is another important type of active filter used in applications. The frequency response of the second-order low pass filter is indistinguishable to that of the first-order type besides that the stopband rolloff will be twice the first-order filters at 40dB/decade A circuit which implements a second order low pass filter is shown below The transfer function of the circuit is given by