Novel design of a low power neural amplifier using split push pull balanced high swing OTA for brain machine interface

This work presents the design of a modified split push–pull balanced (SPPB) operational transconductance amplifier (OTA) for the analog frontend (AFE) of Brain-Machine Interface (BMI) applications. The proposed OTA architecture enables the development of a low-power amplifier with a wide bandwidth and high output swing. Comprehensive post-layout simulations and analyses were conducted in Cadence Virtuoso with reference to the technology library UMC 180 nm and very less deviation is observed between post and pre layout simulation. The simulated results show that the highest gain is 51.66 dB, the average power consumption is 1.69 µW, the phase margin is 60.25 degrees, and the noise level is 918nV/sqrt (Hz) at 1 Hz. Moreover, in this paper using the proposed OTA neural amplifier with capacitive feedback topology is designed which exhibits a maximum mid-band gain of 51.06 dB and a bandwidth ranging from 378.481 mHz to 619.17 Hz. The neural amplifier also found to have acceptable Noise efficiency factor (NEF) which is 2.3. These findings showcase the potential of the neural amplifier with the proposed OTA design for achieving low-power, high-performance amplification in BMI of analog frontends.