A 40Gb/s Transimpedance Amplifier Using Modified Regulated Cascode for Optical Fiber Communication

This paper describes the design of a 40 Gb/s transimpedance amplifier (TIA) for high-density optical fiber communication system. This TIA incorporates modified regulated cascode (RGC), three order intersecting active feedback and passive feedback. Consuming a DC power of 14.5 mW, the single-ended circuit provides a transimpedance gain of 49.5 dB and a -3dB bandwidth up to 40 GHz in IBM 90-nm CMOS technology with a 1.2 V supply. Simulation results show the equivalent input noise current integrated from 1 MHz to 30 GHz is about 6.6 Arms