Abstract—This work presents a low-voltage, low power CMOS symmetrical operational transconductance amplifier (OTA) and its application for realization of a biopotential amplifier in neural recording application. The linear range of OTA is increased by employing multi-tanh differential configuration and source degeneration while the common-mode range is enhanced using DC-shifting scheme. The proposed symmetrical OTA is operated with a single power supply of 0.8 V and shows an open loop gain of 31.6 dB with unit gain bandwidth of 202.3 KHz and using a 7 pF of load capacitor. A neural preamplifier was implemented in moderate inversion region using the proposed OTA. The preamplifier achieves 34.5 dB of gain consuming 77.1 μW of power and has an input referred noise of 24.18 μVrms over 8.9 KHz of bandwidth.

Index Terms—multi-tanh differential pair, low-voltage operational transconductance amplifier, neural preamplifier and moderate inversion

Cite: Shashank Dwivedi and A. K. Gogoi, "A 0.8 V CMOS OTA and Its Application in Realizing a Neural Recording Amplifier," Journal of Medical and Bioengineering, Vol. 4, No. 3, pp. 227-234, June 2015. Doi: 10.12720/jomb.4.3.227-234