A 130-GHz Bandwidth 61-dBOhm Variable-Gain Differential Linear TIA in a 130-nm SiGe:C BiCMOS Technology

A differential linear transimpedance amplifier (TIA) implemented in a 130-nm SiGe:C BiCMOS technology with $f_{\text {T}} / f_{\text {max }}$ of $350 / 450 ~\mathrm{GHz}$ is presented which features a bandwidth of $130 ~\mathrm{GHz}, ~61 ~\mathrm{dBOhm}$ maximum transimpedance (TI) gain and 20-dB gain variability while dissipating 170 mW of DC power. The measured total harmonic distortion (THD) in the maximum gain setting is below 5% for a 750 mVppd output swing and an input current of 600 uApp. To the best of the author’s knowledge, the presented design shows the highest bandwidth among integrated TIAs, while simultaneously demonstrating comparable TI gain, noise characteristics, linearity and DC power consumption compared to state-of-the-art designs.