Simulation Analysis And Research Of Gigabit SFP Optical Transceiver Circuit

Small form-Factor Pluggable Optical Transceiver(SFP) is characterized by functions of small, pluggable and self-diagnoses . Since it requires to integrate optical detector, optical amplifier, optical transmitter, drive and various warning and monitoring control circuits within a small area, however, the difficulty increase correspondingly .With data rate up to 1.25GHZ,it is necessary to consider a serial problems of signal integrity.To solve the problem associated with signal integrity, people more and more depend on use methodology based on circuit simulation , the basic principle is use simulation technology to solve the problem of signal integrity as more as possible in the early design ,put forward the requirement to signal integrity ,timing and EMC/EMI, satisfied manufacture and testing scheme and design principle ,minimize product cost ,reduce the project period.To analyze the simulation of circuit, this context refers to many literature both from home and abroad and discuss the theory of High-Speed circuit and signal integrity, mostly theoretically discuss several basic concepts and the principle of ECL circuit And research the model used for simulation, mainly in the aspects of the cause, behave of the problem of SI as reflection, crosstalk and so on, provide theoretic foundation to analyze and solve problems would meet in the simulation step.Here use Cadence's Allegro interconnection design platform to design SFT optical transceiver circuit. Mainly process pre-simulation and post-simulation on board level .It also analyses the result of simulation by tight the layout rules to signal lines.However, since there are numerous and interlaced variables that drastically affect the SI , here focus on reflection crosstalk and other SI problems of differential input/output lines of SFP .Based on the circuit analysis , through adjusting the board layout to optimize the signal transfer and ensure the signal integrity.