Fully-differential, DC-coupled, self-biased, monolithically-integrated optical receiver in 0.25μm photonic BiCMOS Technology for multi-channel fiber links

A fully-differential receiver structure for fiber links is presented, in which the photodiode (PD) is DC-coupled to the transimpedance amplifier (TIA) and biased through the feedback resistors. The biasing voltage is defined by the internal structure of the input stage. Different options are suggested that allow to adjust PD biasing. Multiple architecture variants are proposed, that were implemented in 0.25μm SiGe BiCMOS technology. Initial measurement results are reported, proving the feasibility of the concept. A 25Gbps hybrid receiver designed to comply with a specific standard is also presented, featuring large horizontal eye opening of 800mV, OMA of -15dBm at BER of 10
^-6
and power dissipation of 330mW from a single 3.3V power supply.