A 92 mW, 20 dB gain, broadband lumped SiGe amplifier with bandwidth exceeding 67 GHz

A compact, power-efficient broadband amplifier is demonstrated in a 0.13-micron SiGe BiCMOS process. The amplifier uses a lumped design topology with a shunt-feedback Darlington input stage and an emitter-follower buffered cascode post-amplifier stage. The overall amplifier consumes 92 mW DC power, and exhibits 20-dB gain. The reported 67-GHz bandwidth is limited by available test equipment, and the post-extraction simulated 3-dB bandwidth is 82 GHz, which implies a gain-bandwidth (GBW) of 820 GHz. The amplifier features a low group delay variation to enable high data rate. The post-extraction simulated group delay is 13+/-2 ps from 1 GHz to 100 GHz. The chip occupies an area of 0.28 mm² including pads, and the core area is only 0.04 mm², which includes all active devices and peaking inductors. This amplifier shows a figure-of-merit GBW/P_dc of 7.3 and 8.9 GHz/mW, assuming bandwidth of 67 GHz and 82 GHz respectively, which are among the best results to date.