0.5 V, 3 6µW Gm-C Butterworth low pass filter in 0.18µm CMOS process

This paper presents a low voltage, low power continuous-time (G_m-C) 4^th order low pass Butterworth filter with a 3-dB bandwidth of 1MHz and capable of operating at supply voltage as low as 0.5V in 0.18 μm. The filter uses bulk-driven technique for achieving the necessary head-room. The simulation results show that the filter has a peak-to-peak signal swing of 1.2V (differential) for 1% THD and a dynamic range of 54 dB. The power consumed by the filter is 36μW when operating at a voltage of 0.5 V. The Figure of Merit (FOM) achieved by the filter is 0.05 fJ and is found to be lowest among the similar filters found in the literature.