A 3-to-13 GHz Quasi-Elliptic Higher-Order N-path Filter

This work presents an on-chip 3rd-order elliptic bandpass N-path filter operating from 3-13 GHz. The filter utilizes the frequency translation of an N-path filter to upconvert the response of a passive LC-based elliptic lowpass filter to realize the higher-order bandpass filtering. The prototype was fabricated in 22nm FDSOI CMOS technology and measures 9.2 dB insertion loss with 3 dB bandwidth of 1.06 GHz at 10 GHz center frequency and a stopband rejection of -20 dB at a frequency offset of 0.89 GHz from the center frequency. The filter achieves a IP1dB and IIP3 of -1.7 dBm, 9.5dBm respectively at 10 GHz center frequency and consumes 25.2mW power at 0.9V supply voltage with an area of 8.6 mm(2).