摘要
This paper discusses the design of a 10 Gb/s laser diode driver implemented in SiGe BiCMOS technology. The laser diode driver is composed of an input buffer, a predriver circuit and an output current switch stage. With the current mode logic （CML） structure, the input buffer and the predriver circuit have the capability of transmission and amplification of high speed data. By employing MOS-HBT cascode structure as the output stage, the laser diode driver exhibits very high speed and efficiency working at the 10 Gb/s data rate. The core circuit is operated under a 3. 3 V supply, while the output stage is operated under 5.5 V for sufficient headroom across the laser diode. The chip occupies a die area of 600 μm × 800μm. Measurements on chip show clear electrical eye diagrams over 10 Gb/s, which can well meet the specifications defined by SDH STM64/SONET OC192 and a 10 Gb/s Ethemet eye mask. Under a 5. 5 V supply voltage, the maximum output swing is 3.0 V with a 50 12 load （the corresponding modulation current is 60 mA）, and the total power dissipation is 660 mW.
讨论一款基于SiGe BiCMOS工艺工作速率为10Gb/s激光驱动芯片的设计.该激光驱动芯片包括输入缓冲、驱动放大电路和输出级电路3个部分.输入缓冲、驱动放大电路采用电流模电路,满足高速数据传输和放大的能力,输出级电路结构采用新型的MOS-HBT共源共栅结构可以降低米勒效应减小输入电容,从而使激光驱动芯片工作在10Gb/s时也能达到良好的性能.主电路电源电压为3.3V,输出级电路供电电压为5.5V,确保激光器有足够的电压摆幅.芯片总面积(包括焊盘)为600μm×800μm,,测试表明当输入10Gb/s的非归零随机码,输出级电源电压为5.5V时,电路总功耗为660mW,在50Ω负载上可以提供3V的驱动电压(相应的驱动电流为60mA).测试眼图清晰,可以很好地满足SDH STM64/SONNET OC192和10Gb/s以太网的模板要求.
基金
The National High Technology Research and Development Program of China(863 Program)(No.2006AA01Z284)
