Research On Analog Front-end Circuit For Optical Receiver Based On SiGe BiCMOS Technology

With the rapid development of the Internet of Things(IoT),cloud computing,and fourth-generation mobile Internet,the data volume and the transmission rate grows dramatically.Due to the high loss and crosstalk,the traditional copper interconnect has become difficult to accommodate the ultra-high-speed data transmission.As an ideal alternative solution,optical interconnection,which chooses the photon as the information carrier,has many advantages,such as low loss,high bandwidth,small crosstalk and no impedance matching,et al.Therefore,it is an inevitable trend of future interconnection.Silicon compatible optical interconnects,which use the architecture similar to the integrated circuits,can significantly improve the integration,manufacturability,and extendibility by utilizing standard technology facilities,experiences,and techniques to design,fabricate,and package optoelectronic integrated circuits.It is an important breakthrough direction for the optical integration in the future.As a key block building of the optical interconnection system,the optical receiver in standard silicon-based process has become a hotspot in the field of optoelectronics.Due to the merits of small power consumption,high integration and low cost,the standard CMOS process has been commonly used to design the optical receiver analog front-end circuit.By contrast,the standard SiGe BiCMOS process has better optical properties,and provides the unique SiGe heterojunction bipolar transistor(HBT)with high transconductance and high bandwidth.Therefore,it is an ideal technology for the broadband optical receiver system.To achieve the wide-band optical receiver analog front-end circuits for the optical interconnection based on the standard silicon-based technology,the research works carried out in this thesis are as following:1.Based on UMC 0.18?m CMOS technology,a novel shunt feedback transimpedance amplifier(TIA)was designed and fabricated.The post measured results shown that the overall gain of the circuit is 58.4dB and the bandwidth of the transimpedance amplifier is 6.9GHz.The average equivalent input noise current is less than 23.8pA/?Hz.The testing results show that the-3dB bandwidth of transimpedance amplifier is 5.2GHz and the average equivalent input noise current density is 21.05pA/ ?Hz.2.Based on IBM 0.18?m SiGe BiCMOS technology,a overall circuit was designed and optimized,including differential transimpedance amplifier with cascode configuration,limiting amplifier with modified Cherry-Hooper configuration,DC offset cancellation circuit consists of an active Miller capacitance and output buffer.Post simulation results indicated that the receiver circuit has a transimpedance gain of 99.3dB? and a bandwidth of 15.2GHz.The equivalent input noise current density of the circuit is under 24.8pA/?Hz.The transmission quality of eye diagram can be guaranteed3.Based on IHP SiGe BiCMOS 0.25?m technology,a overall circuit was designed and optimized,including transimpedance amplifier with bootstrap circuit to eliminate the equivalent input capacitance of the detector,limiting amplifier with Cherry-Hooper configuration,DC offset cancellation circuit consists of an active Miller capacitance,bandgap circuit and output buffer.Post simulation results indicated that the receiver circuit has a transimpedance gain of 77.8dB? and a bandwidth up to 35.6GHz.The fluctuation of group delay is less than 12 ps and the eye diagram is clear and symmetrical.The circuit can satisfy the needs of 25Gb/s ultra high speed transmission.