A DC-to-170GHz Broadband Distributed SPDT-Switch and Power-Combiner Combo with Source Switch Control

This paper presents a CMOS-based DC–170 GHz wideband single-pole double-throw (SPDT) switch and power-combiner module, realized through a distributed topology and a source-controlled switching scheme. Unlike conventional gate-controlled designs, the proposed source-selection approach separates the RF and DC control paths and enhances isolation by enabling an effective negative transistor VGS without the need for negative voltage generation. The distributed two-way combining architecture not only ensures broadband impedance and delay matching, but also enables state-independent operation, allowing seamless reconfiguration between switching and variable gain combining modes within the same network. Fabricated in 22-nm FDSOI CMOS technology, the prototype occupies a compact 0.09 mm² core area and shows close agreement between simulation and measurement. The switch/combiner combo achieves 0–3 dB insertion loss and >15 dB return loss across the entire DC–170 GHz range, demonstrating instantaneous broadband operation without band-tuning or switching elements.