Design and realization of large dynamic range low pass filter with wide tuneable cut-off bandwidth

Abstract

A continuous-time low pass filter (LPF) for high bandwidth application is presented in this paper. The LPF is realized with 6th order Chebyshev structure. Large dynamic range is achieved by adopting linearity enhanced technique. A 6-bit controlled switched-capacitor array is realized to get wide programmable cut-off frequency. The measurement results indicate that the −3 dB cut-off frequency can be tuned from 35 MHz to over 100 MHz. The two-tone test shows that the in-band IM3 can achieve −48 dB with 500 mV pp input swing. This proposed filter is fabricated in TSMC 0.13 μm CMOS technology. It consumes 25 mA current with 3V power supply and occupies 0.5 mm2 area.