2.5Gb/s CMOS RGC Transimpedance Amplifier

A novel low noise CMOS regulated cascode (RGC) transimpedance amplifier, which can be used in the front-end of 2.5Gbit/s optical communication system, is presented. Active inductor peaking technique, active feedback and source follower are used to improve the -3dB bandwidth. Simulation results using 0.18μm standard CMOS process show the transimpedance gain is 71.51dBΩ, the -3dB bandwidth is 2.2GHz, and the average noise current spectral density is 8.3pA/√Hz. When the input current is 35μ A, the output eye-diagram voltage amplitude is 92mV, and the eye-diagram is clean. The power consumption is 10mW.