A 150MHz 3rd-order single Opamp continuous-time analog filter in 28nm CMOS technology

An improved Active-Gm-RC filter architecture is proposed in this paper. With respect to the biquad Active-Gm-RC cell, this architecture exploits the second pole of the Opamp to increase the filter order up to 3, while maintaining single Opamp topology. This reduces the required power per pole. A prototype of the low-pass filter has been designed in 28nm CMOS technology. The filter power consumption is 340μW with a 0.9V voltage supply, cut-off frequency is 150MHz achieving a Figure-of-Merit of 165dB.