A power optimized transconductance amplifier and its application to a 6th order lowpass GmC filter

We present the design of an ultra low power sixth-order Butterworth low pass GmC filter in 0.13µm CMOS process. A method to optimize the power consumption of a fully differential telescopic OTA is also presented to achieve an input linearity of 220 mVpp and transconductance value of 6µS. The OTA is then used to implement an ultra low power filter and to show the impact of parasitic capacitances and resistances on the system. Simulation results shows that the frequency response of the sixth order Butterworth low pass filter is achieved with high precision and a THD of −60dB for 200mVpp input signal is obtained. The overall power consumption is less than 150µW.