A 70 GHz bandwidth low-power active balun employing common-collector resistive feedback in 0.35 µm bipolar SiGe technology

A broadband low-power active balun up to 70 GHz is presented in this work. The active balun employs common-collector resistive feedback that extends its frequency of operation. Furthermore, The active balun consumes low-power of 29.7mW. The amplitude imbalance is less than 2.4 dB, while the phase imbalance is below 7° up to 60GHz and 14° up to 70 GHz. The balun is fabricated in a SiGe 0.35 μm bipolar technology and occupies 0.004 mm², excluding the pads.