A 97-GHz 66-dBΩ SiGe BiCMOS Low-Noise Transimpedance Amplifier for Optical Receivers

In this letter, a transimpedance amplifier (TIA) is presented, which features a bandwidth (BW) of 97 GHz, 66-dB $\mathrm {{{\Omega }}}$ maximum transimpedance gain, and 6.3-pA/ $\mathrm { {\sqrt {Hz}}}$ integrated noise current density, operating at up to 120 Gb/s and consuming only 145 mW. Reaching a higher BW at a noise performance comparable to the state of the art is the novelty of this work. It was achieved by combining a low-BW input stage, reducing the total noise, and a multistage postequalization. The gain peaking technique through cascading emitter follower stages is employed in a broadband TIA as a post equalizer. To the best of our knowledge, the presented design shows the best performance in terms of overall gain, BW, and noise for the lowest power consumption compared to state-of-the-art designs.