High-performance transimpedance formulation for MESFET- and HBT-based monolithic microwave integrated circuits

Analysis of amplifier and feedback combinations leads to the conclusion that the transimpedance configuration offers the opportunity of constant-bandwidth operation. As an example, a transimpedance amplifier based on shunt feedback around a current-gain amplifying element is described, which achieves gain-bandwidth independence at microwave frequencies. Full foundry layout simulation for circuits based on both MESFETs and HBTs indicates that an optical receiver front-end amplifier designed on these principles will exhibit gain-bandwidth independence through the GHz region, with very low sensitivity to photodiode capacitance.