A 20–60 GHz Ultra-Wideband SPDT Switch for Multi-Band Transceivers

A 20-60 GHz ultra-wideband single-pole double-throw (SPDT) switch is demonstrated using reverse-saturated HBTs in a 0.13-μm SiGe BiCMOS technology. A large inductor is connected in the control signal path at the HBT base, which resonates with the internal capacitances of the HBT at an out of band frequency. This way a flat insertion loss response is achieved from 20-60 GHz, broadening the bandwidth of the switch. The realized switch has a minimum insertion loss of 1.7 dB at 40 GHz and less than 3 dB from 20-60 GHz. The input 1-dB compression point is 17 dBm at 32 GHz, and isolation is better than 22.5 dB for the entire band of interest, while the occupied chip area is 0.19 mm ² . The performance of this switch is comparable to any state-of-the-art switches with the advantage of covering most of the frequency band considered for 5G.