Design Of Optical Receiver Front-End Circuit In Standard SiGe BiCMOS

The rapid rise of internet traffic and the need for high capacity data transmissionfor telecommunication network, computer network and Internet network have madeoptical communications the best choice for high speed data transmission through fiberoptical links for both short and long range applications. In addition, high performanceelectronics with electrical interconnects are becoming more and more expensive tomanufacture due to the physical limitations of metal wires and the subsequentcomplexities added to combat them. Issues such as crosstalk, signal propagation delay,and power consumption are becoming the bottlenecks of many systems. On thecontrary, optical interconnection is a good candidate due to its advantage of highbandwidth、no cross-talk、low attenuation and low Electromagnetic Interference.Monolithic optoelectronic integrated circuits(OEIC) occupies an important position inthe above areas, as it converts light signal into electrical signal. Compared to thehybrid-integrated photo-receiver, the monolithic BiCMOS optoelectronic integratedreceiver not only reduces the cost of the receiver greatly, but also improve theperformance of the OEIC.Today, most of high-speed OEIC are based on standard SiGe BiCMOS processfor its performance and cost advantages. Base on the above reasons, an opticalreceiver front-end circuit is designed and fabricated in IBM0.18μm SiGe BiCMOStechnology. The whole circuit consists of a transimpedance amplifier (TIA) withdifferential common-emitter configuration, six limiting amplifiers and an outputbuffer. SiGe heterojunction bipolar transistors (HBTs) having better high-frequencyperformance are used for the differential input pair, thus reduces the equivalent inputresistance, and expands effectively the bandwidth of the optical receiver. Thesimulated results indicate that the optical receiver terminated with50Ω load resistanceand10pF load capacitance has a transimpedance gain of74.59dB, and a-3dBbandwidth of2.39GHz. The optical receiver successfully realizes3Gbit/s data ratewith a bit-error rate of10-9. The fabricated optical receiver has910μm×420μm chiparea, and consumes39.6mW from1.8V supply. The experimental results show thatthe optical receiver front-end achieves a-3dB bandwidth of1.9GHz and successfullyrealizes500Mbit/s data rate with a bit-error rate of10-9.