A Cascaded Distributed Amplifier Operating Up to 110 GHz Using SiGe HBTs

A cascade distributed amplifier (DA) is designed and analyzed in this letter. The proposed DA is fabricated in 0.13 μm SiGe HBTs process and patterned ground micro-strips are deployed for the design of distributed inductors to achieve high-Q in the transmission line (TL). In addition, negative resistors and capacitors are used to widen the bandwidth. Gain boosting techniques are also used to ensure gain flatness throughout the band. The fabricated DA achieves an average gain of 17.5 dB and 14.5 dB gain at 110 GHz. 7.5 and 2.7 dBm saturated output power are obtained at 50 and 100 GHz, respectively. The total chip size is 0.8 mm × 1.8 mm, including the bond pads.