A programmable continuous-time filter

The synthesis of a real-time programmable continuous filter in which both the cutoff frequency and the selectivity are controllable independently over a wide range is described. The approach is based on a circuit topology derived from an LC ladder, and allows the filter to be configured either as low-pass or band-pass. The filter order is easily programmed. A new MOS high-frequency differential integrator with adjustable phase characteristics is presented.<<ETX>>