A tunable low power BiCMOS continuous-time G/sub m/-C lowpass filter

Abstract

A monolithically integrated 5" order lowpass filter with a tunable cutoff frequency is presented The cutoff f'equency can be tuned via a control voltage between 3OWz and I8OWz. This circuit may serve as channel selectingfilters in direct conversion receivers for various cellular radio services with d@erent bandwidth (e.g. IS- 54, GSM etc.). The main design goals are low power consumption. a large tuning range, good linearity and a high dynamic range