Calibration of the Nauta structure differential OTA

In this paper we examine a digitally controllable Nauta structure implemented in a 65nm process and identify a strategy useful for calibrating the structure in such a way that a maximum gain is achieved. We propose an efficient and simple tuning procedure that could be the basis for an integrated on-chip calibration solution and investigate the feasibility of implementing it. The procedure would primarily rely on a digitally implemented control circuit to minimize the need for analogue circuitry and therefore area requirements, and power consumption.