0.5 V, 36μW Gm-C Butterworth Low Pass Filter in 0.18μm CMOS process

Vasantha M. Harishchandra and Tonse Laxminidhi
NITK, Surathkal


This paper presents a low voltage, low power continuous-time (Gm − C) 4th order low pass Butterworth filter with a 3-dB bandwidth of 1 MHz and capable of operating at supply voltage as low as 0.5 V in 0.18 μm. The filter uses bulk-driven technique for achieving the necessary head-room. The simulation results shows that the filter has a peak-to-peak signal swing of 300 mV for 1% THD and a dynamic range of 54 dB. The power consumed by the filter is 36 μW 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 among similar filters found in the literature.