OTA-based dual input integrator

A new type of dual input integrator (ODI) realized with two operational transconductance amplifiers (OTAs) is proposed. A compensation of non-ideally matched characteristics of OTAs, based on dividing the integration period into two subintervals, is achieved. Very high linearity and increased frequency and dynamic range are obtained. The ODI is suitable for measurement of very small time differences between two square-wave input signals.