Reduced size high performance transformer balun at 60 GHz in CMOS 65 nm technology

This paper describes the theoretical study, the design, and the characterization of a novel shape passive balun. The proposed architecture is an evolution of the classical transformer balun with an improving on performances in terms of phase and amplitude balance, and a reduction of the occupied area on the circuit. The proposed balun is designed for 60 GHz applications with a 1 dB bandwidth of 15 GHz around the central frequency. The balun shows a maximum phase and an amplitude imbalance of 8° and 0.2 dB, respectively, in the whole band of interest. The insertion loss is lower than 2 dB. The total occupied area of the component is 0.0071 mm2.