A 1 V 1.2 /spl mu/W 4th order bandpass switched-opamp SC filter for a cardiac pacer sensing stage

Abstract

A 4th-order bandpass switched-capacitor (SC) filter to be used as a part of an implantable device has been designed. The power consumption reduction is a key feature of such a system. This has been achieved by using a 1 V supply (SC operation are guaranteed by using the switched-opamp technique). In addition the active devices operate in the subthreshold region. The filter uses a fully differential topology to reduce the clock feedthrough noise and increase the dynamic range. The filter has been designed in a 0.35 /spl mu/m CMOS technology. It operates at 1 kHz sampling frequency and it consumes about 1.2 /spl mu/W.