Second Order Passive High Pass Filter. Therefore it consists of two reactive components and makes a second order circuit. If we incorporate this passive configuration into the sallen key topology we have the following.
By cascading two first order high pass filters gives us second order high pass filter. Therefore it consists of two reactive components and makes a second order circuit. But in second order high pass filter stop band will be twice that of first order filter at 40db decade.
Second order active high pass filter if we swap the resistor and capacitor in an rc low pass filter we convert the circuit into a cr high pass filter.
Where n is the order or number of stages. Second order high pass filter the frequency response of second order high pass filter is similar to the first order high pass filter. The performance of this two stage filter is equal to single stage filter but the slope of the filter is obtained at 40 db decade. By cascading two first order high pass filters gives us second order high pass filter.
