A Fully-integrated, Low-Power Transimpedance Amplifier for 5Gbps Optical Front-End

This paper presents a three-stage transimpedance amplifier (TIA) for 5Gbps communication applications in 90nm CMOS. The proposed TIA employs an active RGC structure at the input stage, which yields small input resistance, and is followed by a level shifter and a common source structure to obtain extra transimpedance gain at a low supply voltage, while operating at high data rates. Moreover, the proposed TIA is a fully-integrated structure, which introduces a small occupied area on chip. A transimpedance gain of 40.6dBΩ, frequency bandwidth of 3.7GHz, input referred noise of 1.6 μArms (25.3pA/√Hz) and power consumption of 1.3mW is achieved through simulation results in HSPICE using 90nm BSIM4 CMOS technology parameters. Results indicate the proper performance of the proposed circuit as a low-power TIA Front-End.