CMOS Optical Transimpedance Amplifier Design For PAM Signaling Application

Abstract

The advent of Internet telephony and the surge in data communication field necessitate the use of broadband communication systems. The Optical communication systems has been suggested as an attractive solution to cope with the high speed data rate and large throughput bottleneck of the long haul communication systems due to their cheaper deployment cost. In the world of miniaturization, CMOS circuits have been widely used to develop the opto-electronic components. However, the intricacy involved in the design of high speed optical front-end is higher due to the poor noise performance of CMOS circuits compared to their bipolar counter parts. Despite their noise performance, CMOS design facilitates high degree of integration of both analog and digital parts, lower power consumption, and high yield that lowers the fabrication cost. In this thesis, a stand alone high speed differential trans-impedance amplifier serving the front-end of an optical receiver is designed using TSMC 0.18µm mixed-signal non-epi CMOS technology. The design meets the SONET OC-48 standard with 3 different multilevel signaling schemes. The overall trans-impedance gain of 77dBΩ is achieved with 3 post amplifier stages. The eye diagram measurement and power supply parasitic modeling is shown in the simulation.