基于标准BiCMOS工艺的1.5Gbit/s调节型共源共栅光接收机

An integrated 1.5Gbit/s optical receiver fabricated in standard SiGe BiCMOS process

摘要:

基于IBM 0.18μm SiGe Bi CMOS标准工艺设计实现了一种高速、低功耗的光接收机前端模拟电 路。接收机芯片包括调节型共源共栅 (RGC) 跨阻放大器(TIA)、四级限幅放大器(LA)和 输出缓冲 电路(buffer)。采用高跨导SiGe异质结双极晶体管(HBT)作为输入级的RGC TIA有效隔离了 探测器结电容和输入寄生电容的影响,更好地拓展了光接收机的带宽。仿真结果表明,在1.8V电源电 压供电下,驱动50Ω电阻和10pF电容负载时 ,光接收机前端的跨阻增益为76.67dB带宽为2.1GHz 。 测试结果表明,光接收机前端电路的－3dB带宽为1.2GHz,跨阻增 益为72.2dB,在误码率(BER)为10－9的条件 下,光接收机实现了1.5Gbit/s的数据传输速率。在1. 8V电源电压 下,芯片功耗仅为44mW,芯片总面积为800 μm×370μm。

Abstract:

This paper presents a monolithically integrated optical receiver front -end circuit realized with IBM 0.18μm SiGe BiCMOS process.The receiver front-end circuit includes two regula ted cascode trans-impedance amplifiers (RGC-TIAs),four limiting amplifiers and an output buffer.The RGC- TIAs with SiGe heterojunction bipolar transistor (HBT) input stage reduce the input resistance, and isolate the effects of the parasitic photodetector capacitance,thus effectively expand the bandwidth of th e optical receiver.The simulated results indicate that the optical receiver terminated with 50Ω load resistance and 10pF load capacitance has a trans-impedance gain of 76.67dB and a －3dB bandwidth of 2. 1GHz.The experimental results demonstrate that the fabricated receiver achieves a 72.2dB trans-impedance gai n with a 1.2GHz bandwidth,and a data rate of 1.5Gbit/s is successfully realized at a bit-error rate of 10 －9 .Total chip power including the output buffer is 44mW from 1.8V supply,and the chip area including pads is 800μm×370μm.