An Electronic Transimpedance Amplifier for Optical Communication Network Based on Active Voltage-Current Feedback

In this paper , a topology is proposed to realize a new transimpedance amplifier (TIA). The proposed topology reduces the input and output impedances by using a common source transistor as a voltage-current feedback. In this topology instead of using a resistor to convert voltage to current, we convert transistor transconductance into transimpedance, and then by applying an electrical current to drain the required voltage appears at the gate terminal. Furthermore, a TIA circuit is designed on the proposed topology. Simulation of the designed TIA for 1.8V 0.18µm CMOS technology shows that gain of 59dBΩ with 1dBΩ gain ripple of the bandwidth of 10.6GHz can be achieved. While the whole TIA circuit consumes 18mW from 1.8V power supply the simulated average input current noise spectral density is about 21 within the TIA frequency band. Above result is calculated with 300fF parasitic capacitance of photodiode. In this topology new tradeoffs are possible which make a further degree of freedom which are not available in the previous topologies.