Feedforward common gate transimpedance amplifier circuit based on CMOS active inductor in parallel

A modified feedforward common gate transimpedance amplifier circuit was designed. By using CMOS active inductor in parallel with the common source amplifier stage in the feedforward common gate transimpedance amplifier circuit, the bandwidth and gain of the transimpedance amplifier circuit can be improved effectively. Based on TSMC 60 nm CMOS process, simulation analysis and layout design of MFCG cross-resistance amplifier were carried out on Cadence software platform. The simulation results show that when the power supply voltage is 1.8 V and the photodiode junction capacitance is 200 fF, the amplifier circuit's −3 dB bandwidth is 17.2 GHz, the transimpedance gain is 55 dBΩ, the equivalent input noise current spectral density is less than 55 pA /\sqrt \rmHz in the bandwidth, and the circuit power consumption is 3.7 mW. The circuit layout area is 0.0029 mm². The results show that the designed MFCG transimpedance amplifier has the advantages of high transimpedance gain, large bandwidth, small layout area and so on, and can be used in the optical receiver circuit of 20 Gb/s fiber communication system.