Differential transimpedance amplifiers for communications systems based on common-gate topology

A fully new CMOS differential transimpedance preamplifier structure for fiber optics receivers is presented. It is based on the common-gate topology with negative feedback, to increase the bandwidth of the circuit. A bandwidth of 2.30 GHz, with important noise reduction, was achieved. Intermodulation products of 40 dB below the carrier were obtained. Simulations were performed using BSIM3v3 models for HSPICE.