A 1.5 Hz- 15 Hz single ended, fully integrated low pass filter for MEMS interfacing

Abstract

A second order, single ended, fully integrated low pans filter with cut-off frequency tunable in the range 1.5-15 Hz is presented. The filter is based on a recently proposed CMOS transconductor topology, combining Gm values of the order of a few nS with large input ranges and suitability to single-ended filter architectures. The circuit has been designed and fabricated using 3.3 V-0.35 mum CMOS devices from the STMicroelectronics bipolar-CMOS-DMOS process BCD6. The tested prototype occupies a 960 times 350 mum2 area and requires a supply current ranging from 50 to 500 muA, depending on tuning. A dynamic range in excess of 60 dB has been estimated from experimental measurement