On the Design of Broadband Truly Balanced Inductor-Less Differential-to-Single-Ended Converter in CMOS Friendly to Wire-Bond Package

This brief presents a broadband inductor-less differential to single-ended (D2S) converter employing complementary structure with series resistor. The developed D2S converter has a unique advantage in terms of amplitude and phase balance performance, achieving true balance in theory and while maintaining wire-bond package friendliness. The D2S converter is validated in a prototype of broadband driver amplifier (DA) for the transmitter front-end and fabricated in 65 nm CMOS process. The measurement results show an amplitude and phase error of less than 0.2 dB and 1°, respectively, over a frequency range of 0.1 to 6 GHz. The proposed D2S occupies a core chip area of only $0.04\times0.1$ mm ² and consumes $6.5-7.4$ mW power from a 1.2 V supply voltage.