Ultra low power active-RC filter in 180 nm CMOS technology

This paper presents the design of a low voltage, ultra low power fifth order Chebyshev low pass filter operating at a power supply voltage of 0.5 V in 180 nm CMOS technology. A CMOS inverter based transconductor is used as the building block. A sub-threshold model is developed for the transconductor as the transistors are operating in sub-threshold region. A feedforward compensated OTA is designed using this transconductor and is used to realize the filter. Designed filter has a cutoff frequency of 150 kHz and offers a dynamic range of 54.16 dB with a figure of merit of 0.02 fJ. Power consumed by the filter is 21.79 microwatt.