Low-noise OTA for neural amplifying applications

Abstract

This paper presents an ultra low-power operational transconductance amplifier (OTA), which can be used in the implementation of preconditioning stage of implantable neural recording microsystems. In such applications, low-noise performance is both critical and challenging especially at very low power consumptions. By means of a new structure for OTA, a low-noise, low-power, and small-silicon-area OTA is proposed. The OTA was designed in a 0.5-μm standard 2P3M N-Well CMOS process. Simulation results for the proposed OTA show an open-loop gain of 62dB, unity-gain bandwidth of 4MHz, and 59nVrms/√Hz input-referred noise. Power dissipation of the OTA is as low as 4μW at 3-V supply voltage.