Analysis of Multistage Feedforward Operational Transconductance Amplifiers using Single-Pole Approximation

This paper presents analysis results of the operational transconductance amplifiers (OTAs) that combine feedforward paths and multistage amplifiers to achieve high-gain wideband operation as well as frequency compensation. To analyze multistage feedforward OTAs and provide an intuitive design method, the single-pole approximation model is employed for each substage of the OTA. Using the single-pole approximation model, the analysis is carried out from the two-stage OTA to the four-stage OTA in this work.