A 234-261-GHz 55-nm SiGe BiCMOS Signal Source with 5.4-7.2 dBm Output Power, 1.3% DC-to-RF Efficiency, and 1-GHz Divided-Down Output.

A 234-261-GHz signal source with record 7.2-dBm output power at 240 GHz and -105 dBc/Hz phase noise at 10-MHz offset is reported. Fabricated in a production 55-nm SiGe BiCMOS process with HBT fT/fMAX of 330/350 GHz, the circuit includes a 120-GHz fundamental frequency VCO with 1.2-V AMOS varactors, a broadband MOS-HBT cascode LO tree driving a divide-by-128 chain, and a doubler with a record drain...