A 60-GHz CMOS Down-Conversion Mixer with Current-Reused RF Single-to-Differential Converter and Integrated Marchand Balun

A 60-GHz double-balanced mixer for direct down-conversion using standard 90-nm CMOS technology is reported. The down-conversion mixer comprises a double-balanced Gilbert cell with a current-reused RF single-to-differential converter for conversion gain (CG) enhancement, a Marchand balun for converting the single LO input signal to differential signal, and a baseband amplifier. The mixer consumes 17 mW and achieves low noise figure of 12.8 dB at 60 GHz. In addition, the mixer achieves excellent LO-RF isolation of 64.7 dB, LO-IF isolation of 51.5 dB, and RF-IF isolation of 59.5 dB at RF of 60 GHz and LO of 59.9 GHz. At IF of 0.1 GHz, the mixer achieves maximum CG of 15.46 dB at RF of 62 GHz, and CG of 14.7 dB at RF of 60 GHz, one of the best CG results ever reported for a 60-GHz CMOS down-conversion mixer. The corresponding 3-dB bandwidth of RF is 5.4 GHz (58.7-64.1 GHz). These results demonstrate the proposed down-conversion mixer architecture is very promising for 60-GHz direct-conversion transceiver applications. (c) 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1937-1946, 2013