5.4.3 Types offilters H(f) For simple first-order systems, the attenuation √2 is quite gradual with frequency 6dB/octave 1/2πr By adding more"stages P(f) 1/2xr 0 (see Fig. 5.42(a)the 45 sharpness of cutoff may be increased. But the 0)° disadvantage: loading effects should be take Fig. 5.41 Amplitude and phase characteristics of the first-order Into account low-pass filters5.4.3 Types of filters For simple first-order systems, the attenuation is quite gradual with frequency,6dB/octave. By adding more “stages” (see Fig.5.42(a))the sharpness of cutoff may be increased. But the disadvantage: loading effects should be take into account. Fig. 5.41 Amplitude and phase characteristics of the first-order low-pass filters