Active-error feedforward technique for linearization of cmos transconductance amplifier

In the paper, a novel highly linear operational transconductance amplifier (OTA) is proposed. The circuit is developed using simple differential pair transconductors and linearization technique based on an active-error feedforward concept. As a result, improved linearity of the single-input two-output OTA is obtained. SPICE simulations show that for the circuit working with a +/- 1.25V power supply, total harmonic distortion (THD) at 0.6V(pp) is less then 0.38% in comparison to 10.0% without linearization. Moreover, the input voltage range of linear operation is increased. Power consumption of the overall circuit is 0.3mW. As an example, the linearized OTA is used to design a highly linear G(m),-C filter that implements 5(th) order Butterworth low-pass transfer function.