Folded-cascode transimpedance amplifiers employing a CMOS inverter as input stage

This paper presents the design and comparison of two shunt feedback transimpedance amplifiers (TIAs) implemented in standard 350nm CMOS technology from Austria Microsystems. These transimpedance amplifiers are based on a folded cascode topology. The first one is a conventional folded-cascode (CFC-TIA) and the second is a modified version folded-cascod (MFC-TIA) employing a CMOS inverter at the input stage. The proposed MFC-TIA achieves a gain of 80dBΩ, 370MHz bandwidth and minimum input current noise of 1,6pA√Hz with 0.5pF total input capacitance. The achieved results show that MFC-TIAs can match the performance of CFC-TIAs with reduced implementation area, thus being a suitable solution for photo-detector array receivers.