A DC to 40 GHz 4-Vpp output high-efficiency linear driver for optical communication

This paper presents a low-power high-efficiency linear driver for optical modulators in a 0.25-m SiGe: C BiCMOS technology. The driver features a small-signal gain of 18 dB and a 3-dB bandwidth of 40 GHz and delivers a maximum output amplitude of 4 Vpp to a 100 differential load. With the inductor-peaking method, this driver achieves 34 ps ± 3 ps group delay from DC to 50 GHz. For time-domain measurement, this driver achieves a symbol rate of 56 Gb/s NRZ and 28.05 Gbaud PAM4 limited by measurement platform limitations while it has potential to achieve 50 Gbaud PAM4 from design analysis and S-parameter measurement. The bandwidth/fT ratio is 22.2%, the power efficiency is 4%, and the power consumption is 499 mW which is 40% lower than the state-of-the-art.