Implementation of active distributed RC anti-aliasing/smoothing filters

The design of an active distributed RC filter is described for use as an anti-aliasing/smoothing filter in a PCM channel bank filter. A new filter configuration (known as a Rauch filter) has been chosen which uses the op amp in inverting configuration with a zero common mode signal and thus results in improved high-frequency attenuation characteristics along with good power supply rejection. A conventional Sallen and Key configuration with distributed RC elements is also discussed.