1.5 V High Performance S.C. Filters in BiCMOS Technology

Line fed telecommunication circuits like battery operated circuits must work from very low supplies. Contrary to most battery operated systems in telecommunication applications, high performance is also required. This paper describes two low voltage (1.5 V minimum) Switched Capacitor (S.C.) filters that achieve a dynamic range comparable with that of filters operated from 5V or more. Both filters use a fully differential architecture and are fabricated on a standard BiCMOS technology. Measured performance from a 2 V supply are a SNR of 92 dB and a THD of -70 dB for a 2.4 Vpp differential signal. Power consumption and area per pole are 60 μW and 300 mil² respectively with a clock frequency of 480 kHz.