A low power mixer with LC phase shifters for a single-end input

In this paper, a silicon downconversion mixer with a pairs of LC phase shifters using a TSMC 0.18um CMOS technology is demonstrated. In this circuit, the lower source-coupled pair in a traditional Gilbert cell mixer is displaced by two sets of LC phase shifters to enable low voltage and low power operation. The simulated results show the conversion gain (CG) of 7.9 dB, the input third-order intercept point (IIP3) of 2.5 dBm, the noise figure of 9.4 dB at the frequency of 1.9 GHz. The measured CG and IIP3 is 8.7 dB and 6 dBm at the frequency of 1.9 GHz. The measured NF is 15 dB. The simulated and measured power consumption is 1.97 mW and 2.72 mW respectively, under the supply voltage of 1.6 V.