ABSTRACT
In this chapter we present a different approach to the design of active filters, namely, the use of the entire passive RC network to provide the feedback around the operational amplifier. A general configuration for the second-order case is shown in Figure 3.1. It is called a multifeedback infinite gain amplifier filter. The resulting transfer function is an inverting one, i.e., the dc gain is negative. With this configuration we can have a low-pass, a high-pass, and narrow-band band-pass characteristic.
